The 1955 Formula One season was the ninth season of FIA Formula One motor racing. It featured the sixth World Championship of Drivers, which was contested over seven races between 16 January and 11 September 1955. The season also included several non-championship races for Formula One cars.

Juan Manuel Fangio won his second consecutive World Championship title.^[1] It was his third in total, a record that would not be beaten until Alain Prost in 1993. This was the last championship for a Mercedes driver until 2014.

The season was coloured by tragedy. Two drivers were killed during the 1955 Indianapolis 500: Manny Ayulo and Bill Vukovich, winner of the two previous editions.^[2] Italian Mario Alborghetti died at the non-championship Pau Grand Prix. Alberto Ascari, World Champion of 1952 and 1953, was killed while testing a Ferrari 750 Monza at Monza.^[3][4][5] And ex-Formula One driver Pierre Levegh was killed in the 1955 Le Mans disaster, along with 83 spectators. This would lead to the cancellation of four F1 Grands Prix.

The following teams and drivers competed in the 1955 FIA World Championship. The list does not include those who only contested the Indianapolis 500.

Entrant	Constructor	Chassis	Engine	Tyre	Driver	Rounds
Daimler Benz AG	Mercedes	W196	Mercedes M196 2.5 L8	C	Juan Manuel Fangio	1–2, 4–7
					Karl Kling	1, 4–7
					Stirling Moss	1–2, 4–7
					Hans Herrmann	1–2
					André Simon	2
					Piero Taruffi	6–7
Scuderia Ferrari	Ferrari	625 555	Ferrari 555 2.5 L4	E	Umberto Maglioli	1, 7
					José Froilán González	1
					Maurice Trintignant	1–2, 4–7
					Harry Schell	2, 4
					Piero Taruffi	2, 4
					Paul Frère	2, 4
					Mike Hawthorn	5–7
					Eugenio Castellotti	5–7
					Giuseppe Farina	1–2, 4
	Lancia	D50	Lancia DS50 2.5 V8			7
Officine Alfieri Maserati	Maserati	250F	Maserati 250F1 2.5 L6	P	Jean Behra	1–2, 4–7
					Roberto Mieres	1–2, 4–7
					Sergio Mantovani	1
					Luigi Musso	1–2, 4–7
					Carlos Menditeguy	1, 7
					Clemar Bucci	1
					Harry Schell	1
					Cesare Perdisa	2, 4
					André Simon	6
					Peter Collins	7
					Horace Gould	7
Alberto Uría	Maserati	A6GCM	Maserati 250F1 2.5 L6	P	Alberto Uría	1
Scuderia Lancia	Lancia	D50	Lancia DS50 2.5 V8	P	Alberto Ascari	1–2
					Luigi Villoresi	1–2, 7
					Eugenio Castellotti	1–2, 4
					Louis Chiron	2
Equipe Gordini	Gordini	T16	Gordini 23 2.5 L6	E	Élie Bayol	1–2
					Pablo Birger	1
					Jesús Iglesias	1
					Robert Manzon	2, 5–6
					Jacques Pollet	2, 5, 7
					Hermano da Silva Ramos	5–7
					Mike Sparken	6
					Jean Lucas	7
Ecurie Rosier	Maserati	250F	Maserati 250F1 2.5 L6	P	Louis Rosier	2, 4–5
Vandervell Products	Vanwall	VW 55	Vanwall 254 2.5 L4	P	Mike Hawthorn	2, 4
					Ken Wharton	6–7
					Harry Schell	6–7
Stirling Moss Ltd	Maserati	250F	Maserati 250F1 2.5 L6	D	Lance Macklin	2, 6
					Johnny Claes	4
					Peter Walker	5
					John Fitch	7
E.N. Whiteaway	HWM-Alta	53	Alta GP 2.5 L4	D	Ted Whiteaway	2
Equipe Nationale Belge	Ferrari	625	Ferrari 625 2.5 L4	E	Johnny Claes	5
Gould's Garage (Bristol)	Maserati	250F	Maserati 250F1 2.5 L6	D	Horace Gould	5–6
Connaught Engineering	Connaught-Alta	B	Alta GP 2.5 L4	D	Kenneth McAlpine	6
					Jack Fairman	6
R.R.C. Walker Racing Team	Connaught-Alta	B	Alta GP 2.5 L4	D	Tony Rolt	6
					Peter Walker	6
Leslie Marr	Connaught-Alta	B	Alta GP 2.5 L4	D	Leslie Marr	6
Cooper Car Company	Cooper-Bristol	T40	Bristol BS1 2.0 L6	D	Jack Brabham	6
Owen Racing Organisation	Maserati	250F	Maserati 250F1 2.5 L6	D	Peter Collins	6
Gilby Engineering	Maserati	250F	Maserati 250F1 2.5 L6	D	Roy Salvadori	6
Scuderia Volpini	Arzani-Volpini-Maserati	F1	Maserati 4CLT 2.5 L4	P	Luigi Piotti	7

• Stirling Moss moved from Maserati to Mercedes, like Juan Manuel Fangio had done already during the 1954 season.
• Maserati hired Jean Behra from Gordini, after which the French team reunited with Robert Manzon, their driver from 1953 and the years before.
• Vanwall hired Mike Hawthorn from Ferrari, so Peter Collins moved to Owen Racing Organisation, which would later become British Racing Motors.
• Lancia had made their debut at the end of 1954 and entered the 1955 season with full-time ambitions. They were able to hire top-class drivers Alberto Ascari, Luigi Villoresi and Eugenio Castellotti.

• Maserati driver Sergio Mantovani lost a leg in a crash during practice for the non-championship Valentino Grand Prix.^[6] The team hired Cesare Perdisa, who finished third on his debut.
• Peter Collins had been driving a Maserati 250F for Owen Racing Organisation when Maserati's team leader, impressed with his results, offered him a seat at the works team, starting at the Italian Grand Prix.^[7][8] However, Collins parted with the team after just one race, as Ferrari offered him a seat for 1956.
• André Simon substituted for Mercedes driver Karl Kling in the Monaco Grand Prix.
• Double World Champion Alberto Ascari lost his life while testing a Ferrari 750 Monza at Monza. Along with serious financial troubles, this led to Lancia's team owner to halt operations and hand all assets to Enzo Ferrari.^[9][10] Ferrari brought back Mike Hawthorn to drive, after the Brit had spent half a year with Vanwall.
• The 1955 24 Hours of Le Mans did not only see tragedy during the race: in Friday practice, Élie Bayol (driving in F1 for Gordini) had to avoid two spectators crossing the road. This caused him to have a severe crash, suffering a fractured skull and broken vertebrae.^[11] He was out of racing for the rest of the year, so the Gordini team hired sports car and rally driver Hermano da Silva Ramos.
• Gordini's team manager Jean Lucas took the wheel in the Italian Grand Prix, because Robert Manzon was unavailable.

Round	Grand Prix	Circuit	Date
1	Argentine Grand Prix	Autódromo Oscar Alfredo Gálvez, Buenos Aires	16 January
2	Monaco Grand Prix	Circuit de Monaco, Monte Carlo	22 May
3	Indianapolis 500	Indianapolis Motor Speedway, Speedway	30 May[a]
4	Belgian Grand Prix	Circuit de Spa-Francorchamps, Stavelot	5 June
5	Dutch Grand Prix	Circuit Zandvoort, Zandvoort	19 June
6	British Grand Prix	Aintree Motor Racing Circuit, Merseyside	16 July
7	Italian Grand Prix	Autodromo Nazionale di Monza, Monza	11 September

• The Monaco and Dutch Grand Prix returned to the calendar after they had been run for the last time in 1952 and 1953, respectively.
• The British Grand Prix was moved from Silverstone to Aintree, in keeping with the event-sharing arrangement between the two circuits.

In the aftermath of the 1955 Le Mans disaster, it was decided to reschedule the French Grand Prix from 3 July to 25 September.^[12] It was later cancelled, along with the German, Swiss and Spanish rounds.^[13][14]

Grand Prix	Circuit	Original date
French Grand Prix	Reims-Gueux, Gueux	3 July
German Grand Prix	Nürburgring, Nürburg	31 July
Swiss Grand Prix	Circuit Bremgarten, Bern	21 August
Spanish Grand Prix	Pedralbes Circuit, Barcelona	23 October

The circuits at Pedralbes and Bremgarten were never used again for racing. Motor racing was banned altogether in Switzerland until the 2018 Zürich ePrix.

For the third year in a row, the championship opened with the Argentine Grand Prix. José Froilan González started on pole position. The Argentine had been a full-time Ferrari driver in 1954, but it would be his only race this year. Next to him on the front row started two double World Champions: Alberto Ascari in the Lancia and Juan Manuel Fangio in the Mercedes. Fangio took the lead at the start, but lost it to Ascari on lap 3. Teammate Stirling Moss went from eighth to third, while behind them, drivers and cars were beginning to succumb to the heat of 52 °C (126 °F). On lap 21, Ascari crashed out by himself, leaving González in the lead. However, he was still recovering from his accident in the 1954 RAC Tourist Trophy and got exhausted. Fearing he could not hold Fangio behind, he pitted to hand the car to teammate and 1950 World Champion Nino Farina. Fangio pitted as well, for new tyres and to cool off, while Moss retired due to a vapor lock in the fuel pump. This left another local driver, Roberto Mieres in the Maserati, in the lead after starting sixteenth. Sadly, his fuel pump faltered as well and he spent 10 minutes in the pits, coming home in fifth. Besides Mieres, Fangio would be the only classified driver not to have switched cars during the race, and went on to win. Two Ferraris completed the podium, but each had seen three different drivers behind the wheel, so Fangio had an immediate lead in the championship.^[15][16]

The Monaco Grand Prix returned to the calendar after three years and was given the honorary title of European Grand Prix. A new rule to qualifying had been added: only the times recorded in the first practice session on Thursday afternoon would count for the front row of the grid and, thus, for pole position. The rest of the starting places would be decided by the remaining sessions on Friday and Saturday morning. This was done to entice spectators to come and watch every session, but it was an unpopular idea with the drivers. Fangio set the fastest time, ahead of Ascari and Moss, so they could relax and use the remaining sessions to try out car set-ups for the race. At the start of the race, Fangio held on to the lead, but Ascari fell back. Moss took second place after a few laps and was slowly closing up to his teammate in front. After the two drivers behind Moss pitted, Ascari was left in a lonely third place until, at half-distance, Fangio stopped on track with a broken transmission and, on lap 81, Moss's engine blew up. Ascari took the unexpected lead of the race, but mere seconds later, crashed coming out of the harbour chicane and plunged into the water. He was lucky to escape with just a cut on the nose. Maurice Trintignant took the win for Ferrari, the first of his career, ahead of Eugenio Castellotti for Lancia and Cesare Perdisa in Jean Behra's Maserati.^[17]

The Indianapolis 500 was included in the Formula One championship, but no F1 drivers attended. Bob Sweikert won the race.

In the Drivers' Championship, Maurice Trintignant (Ferrari) was leading with 11 points, ahead of Juan Manuel Fangio (Mercedes) with 10 and Bob Sweikert (Kurtis Kraft) with 8. Sweikert would not compete in any other rounds.

Four days after the Monaco Grand Prix, double World Champion Alberto Ascari was tragically killed in a test session at Monza. Further burdened by financial troubles, the Lancia team was left with two cars and just one driver. Soon, all assets would be merged into the Ferrari team, but this did not stop Eugenio Castellotti from scoring his first career pole position in the Belgian Grand Prix. The Mercedes cars of Juan Manuel Fangio and Stirling Moss started beside him on the front row. Championship leader Maurice Trintignant started down in eleventh out of thirteen. At the start, Fangio and Moss quickly took the lead and never looked back. Castellotti retired on lap 16, allowing 1950 World Champion Nino Farina to finish third for Ferrari.^[18]

On 11 June, the 24 Hours of Le Mans took place and many F1 drivers participated. During the race, Pierre Levegh crashed into the spectator area, killing 83 people and injuring at least 120 others. This led the FIA to postpone the French Grand Prix.^[12] However, the Dutch Grand Prix was next on the F1 championship and went on undisturbed. Mercedes managed to occupy the front row with Fangio, Moss and Karl Kling. At the start, Luigi Musso put his Maserati into second position, but was outbraved by Moss. Kling tried his best to keep up with the leading trio but, on lap 21, spun off and retired. Fangio and Moss scored another one-two finish, a minute ahead of Musso. This was the first race since the 1950 French Grand Prix that none of the cars on the podium were powered by a Ferrari engine.^[19]

For the British Grand Prix, Stirling Moss scored his first career pole position in front of his home crowd. Fangio started second, Jean Behra third for Maserati. The second row was filled by two more Mercedes: Karl Kling and Piero Taruffi. Fangio had the best start, but Moss regained the lead on lap 3, his car set up with a lower top speed but better acceleration out of the corners. Behra retired on lap 10, handing the top four positions to Mercedes, with Fangio once again in front. A couple of laps later, Moss retook the lead, grew his advantage to ten seconds and set a new lap record. Unused to having the team leader behind him, Moss looked back on the last lap and hesitated. But Fangio hang back, two tenths behind, leaving the home hero to take the win.^[20]

In the Drivers' Championship, Juan Manuel Fangio (Mercedes) led with 33 points, ahead of Stirling Moss (Mercedes) with 22 and Maurice Trintignant (Ferrari) with 11 points. After the British Grand Prix, the German, Swiss, French and Spanish Grand Prix were cancelled, in the aftermath of the 1955 Le Mans disaster. This left just one race in the championship and effectively handed the title to Fangio.

The Italian Grand Prix was run on the 10 km (6.2 mi) Monza layout including a new steep banking. Nino Farina crashed in practice when his rear tyre came apart under the load of the banked turn and the heat of the sun. He escaped unhurt but his Ferrari-run Lancia was written off, and although Sunday was substantially cooler, the other Lancia was withdrawn as a precaution. Like in Zandvoort, Mercedes-Benz in Formula One#Mercedes occupied the front row in the order of Fangio, Moss, Kling. Moss took the lead at the start, but gave way to his Argentinian team leader before the first lap was run. The fourth Mercedes of Taruffi went from ninth to fourth, the team repeating their procession run from last race. However, Moss pitted on lap 19 for a new windscreen and subsequently retired on lap 28 when his engine cut out. Kling's gearbox broke and he retired as well, leaving the German team worried, but Fangio and Taruffi finished the race untroubled, scoring another Mercedes 1-2, ahead of Eugenio Castellotti for Ferrari.^[21]

Juan Manuel Fangio (Mercedes) had collected 40 points and won his third Drivers' Championship, his second in a row. Teammate Stirling Moss was second with 23 points and Eugenio Castellotti third with 12. Mercedes withdrew from F1 after this season, marking it the final race until the team's revival in 2010, their final win until the 2012 Chinese Grand Prix and final championship title until 2014.

Round	Grand Prix	Pole position	Fastest lap	Winning driver	Winning constructor	Tyre	Report
1	Argentine Grand Prix	José Froilán González	Juan Manuel Fangio	Juan Manuel Fangio	Mercedes	C	Report
2	Monaco Grand Prix	Juan Manuel Fangio	Juan Manuel Fangio	Maurice Trintignant	Ferrari	E	Report
3	Indianapolis 500	Jerry Hoyt	Bill Vukovich	Bob Sweikert	Kurtis Kraft-Offenhauser	F	Report
4	Belgian Grand Prix	Eugenio Castellotti	Juan Manuel Fangio	Juan Manuel Fangio	Mercedes	C	Report
5	Dutch Grand Prix	Juan Manuel Fangio	Roberto Mieres	Juan Manuel Fangio	Mercedes	C	Report
6	British Grand Prix	Stirling Moss	Stirling Moss	Stirling Moss	Mercedes	C	Report
7	Italian Grand Prix	Juan Manuel Fangio	Stirling Moss	Juan Manuel Fangio	Mercedes	C	Report

Points were awarded to the top five classified finishers, with an additional point awarded for setting the fastest lap, regardless of finishing position or even classification. Only the best five results counted towards the championship. Shared drives result in shared points for each driver if they finished in a points-scoring position. If more than one driver set the same fastest lap time, the fastest lap point would be divided equally between the drivers. Numbers without parentheses are championship points; numbers in parentheses are total points scored. Points were awarded in the following system:

Pos. Driver ARG MON 500 BEL NED GBR ITA Pts. 1 Juan Manuel Fangio 1F (RetPF) 1F 1P 2 1P 40 (41) 2 Stirling Moss 4† / Ret 9 2 2 1PF RetF 23 3 Eugenio Castellotti Ret† 2 RetP 5 6† / Ret 3 12 4 Maurice Trintignant 2† / 3† / Ret 1 6 Ret Ret 8 11 1⁄3 5 Nino Farina 2† / 3† 4 3 DNS 10 1⁄3 6 Piero Taruffi 8† DNS 4 2 9 7 Bob Sweikert 1 8 8 Roberto Mieres 5 Ret 5† 4F Ret 7 7 9 Jean Behra 6† / Ret† / Ret 3† / Ret† 5† / Ret 6 Ret 4 6 10 Luigi Musso 7† / Ret† Ret 7 3 5 Ret 6 11 Karl Kling 4† / Ret Ret Ret 3 Ret 5 12 Jimmy Davies 3 4 13 Tony Bettenhausen 2† 3 14 Paul Russo 2† 3 15 Paul Frère 8† 4 3 16 Johnny Thomson 4 3 17 José Froilán González 2†P 2 18 Cesare Perdisa 3† / Ret† 8 2 19 Luigi Villoresi Ret† / Ret 5 DNS 2 20 Carlos Menditeguy Ret† / Ret 5 2 21 Umberto Maglioli 3† 6 1 1⁄3 22 Hans Herrmann 4† DNQ 1 23 Walt Faulkner 5† 1 24 Bill Homeier 5† 1 25 Bill Vukovich RetF 1 — Mike Hawthorn Ret Ret 7 6† 10 0 — Harry Schell 6† / 7† / Ret† Ret DNS 9† / Ret Ret 0 — Louis Chiron 6 0 — Andy Linden 6 0 — Jacques Pollet 7 10 Ret 0 — Al Herman 7 0 — Mike Sparken 7 0 — Sergio Mantovani 7† / Ret† 0 — Hermano da Silva Ramos 8 Ret Ret 0 — Lance Macklin DNQ 8 0 — Pat O'Connor 8 0 — Louis Rosier Ret 9 9 0 — Ken Wharton 9† Ret 0 — Jimmy Daywalt 9 0 — John Fitch 9 0 — Pat Flaherty 10 0 — Duane Carter 11 0 — Johnny Claes DNS 11 0 — Chuck Weyant 12 0 — Eddie Johnson 13 0 — Jim Rathmann 14 0 — Robert Manzon Ret Ret Ret 0 — Horace Gould Ret Ret Ret 0 — Alberto Ascari Ret Ret 0 — Élie Bayol Ret Ret 0 — André Simon Ret Ret 0 — Peter Collins Ret Ret 0 — Peter Walker Ret Ret† 0 — Jesus Iglesias Ret 0 — Pablo Birger Ret 0 — Alberto Uría Ret 0 — Don Freeland Ret 0 — Cal Niday Ret 0 — Art Cross Ret 0 — Shorty Templeman Ret 0 — Sam Hanks Ret 0 — Keith Andrews Ret 0 — Johnnie Parsons Ret 0 — Eddie Russo Ret 0 — Ray Crawford Ret 0 — Jimmy Bryan Ret 0 — Jack McGrath Ret 0 — Al Keller Ret 0 — Johnny Boyd Ret 0 — Ed Elisian Ret 0 — Rodger Ward Ret 0 — Jerry Hoyt RetP 0 — Jimmy Reece Ret 0 — Fred Agabashian Ret 0 — Kenneth McAlpine Ret 0 — Jack Brabham Ret 0 — Roy Salvadori Ret 0 — Leslie Marr Ret 0 — Jean Lucas Ret 0 — Clemar Bucci Ret† 0 — Tony Rolt Ret† 0 — Ted Whiteaway DNQ 0 — Jack Fairman DNS 0 — Luigi Piotti DNS 0 Pos. Driver ARG MON 500 BEL NED GBR ITA Pts.

Key Colour Result Gold Winner Silver Second place Bronze Third place Green Other points position Blue Other classified position Not classified, finished (NC) Purple Not classified, retired (Ret) Red Did not qualify (DNQ) Black Disqualified (DSQ) White Did not start (DNS) Race cancelled (C) Blank Did not practice (DNP) Excluded (EX) Did not arrive (DNA) Withdrawn (WD) Did not enter (empty cell) Annotation Meaning P Pole position F Fastest lap

• † Position shared between multiple drivers of the same car.

Other Formula One races were also held in 1955, which did not count towards the World Championship.

Race name	Circuit	Date	Winning driver	Constructor	Report
VII Gran Premio del Valentino	Valentino Park	27 March	Alberto Ascari	Lancia	Report
XVI Pau Grand Prix	Pau	11 April	Jean Behra	Maserati	Report
III Glover Trophy	Goodwood	11 April	Roy Salvadori	Maserati	Report
IV Grand Prix de Bordeaux	Bordeaux	25 April	Jean Behra	Maserati	Report
VII BRDC International Trophy	Silverstone	7 May	Peter Collins	Maserati	Report
VIII Gran Premio di Napoli	Posillipo	8 May	Alberto Ascari	Lancia	Report
XVII Grand Prix d'Albi	Albi (Les Planques)	29 May	André Simon	Maserati	Report
III Curtis Trophy	Snetterton	29 May	Roy Salvadori	Maserati	Report
III Cornwall MRC Formula 1 Race	Davidstow	30 May	Leslie Marr	Connaught-Alta	Report
III London Trophy	Crystal Palace	30 July	Mike Hawthorn	Maserati	Report
III Daily Record Trophy	Charterhall	6 August	Bob Gerard	Maserati	Report
III RedeX Trophy	Snetterton	13 August	Harry Schell	Vanwall	Report
II Daily Telegraph Trophy	Aintree	3 September	Roy Salvadori	Maserati	Report
II International Gold Cup	Oulton Park	24 September	Stirling Moss	Maserati	Report
I Avon Trophy	Castle Combe	1 October	Harry Schell	Vanwall	Report
V Gran Premio di Siracusa	Syracuse	23 October	Tony Brooks	Connaught-Alta	Report