Men's singles
2001 AIG Japan Open Tennis Championships
Final
Champion	Lleyton Hewitt
Runner-up	Michel Kratochvil
Score	6–4, 6–2
Details
Draw	56 (7 Q / 5 WC )
Seeds	16
Events
Singles men women Doubles men women
← 2000 · Japan Open · 2002 →

Sjeng Schalken was the defending champion but lost in the quarterfinals to Michel Kratochvil.

Lleyton Hewitt won in the final 6–4, 6–2 against Kratochvil. With the victory, Hewitt became the last male player to win his debut event as a Grand Slam champion (having recently won the US Open) until Jannik Sinner in 2024.^[1]

The top eight seeds received a bye to the second round.

	Semifinals							Final
	1	Lleyton Hewitt	6	6
		James Blake	4	0
								1	Lleyton Hewitt	6	6
								5	Michel Kratochvil	4	2
		Karol Kučera	0	3
	5	Michel Kratochvil	6	6

	First round							Second round							Third round							Quarterfinals
								1	L Hewitt	6	6
		J Delgado	4	4					M-K Goellner	2	2
		M-K Goellner	6	6											1	L Hewitt	6	6
	Q	J Thomas	3	2											15	M Russell	1	1
		C Mamiit	6	6					C Mamiit	6	4	3
		N Godwin	4	61				15	M Russell	3	6	6
	15	M Russell	6	77																		1	L Hewitt	4	6	6
	11	N Massú	6	6																		8	F Clavet	6	4	2
		E Kempes	4	4				11	N Massú	6	77
		Y-I Yoon	3	1					T Zíb	3	64
		T Zíb	6	6											11	N Massú	3	4
		N Thomann	3	1											8	F Clavet	6	6
		T Behrend	6	6					T Behrend	67	2
								8	F Clavet	79	6

	First round							Second round							Third round							Quarterfinals
								4	J Björkman	6	6
	Q	M Onoda	4	4				WC	H Kondo	1	3
	WC	H Kondo	6	6											4	J Björkman	1	5
		J Blake	6	6												J Blake	6	7
	WC	Y Ishii	3	4					J Blake	77	7
	Q	R Žitko	2	77	1			14	W Arthurs	64	5
	14	W Arthurs	6	63	6																		J Blake	4	6	6
	10	H Levy	6	6																		7	M Ríos	6	4	1
	Q	S Iwabuchi	3	3				10	H Levy	5	0
	Q	D Udomchoke	6	4	6			Q	D Udomchoke	7	6
		B Cowan	2	6	3										Q	D Udomchoke	3	2
		B Black	6	6											7	M Ríos	6	6
		E Taino	4	1					B Black	2	5
								7	M Ríos	6	7

	First round							Second round							Third round							Quarterfinals
								6	M Chang	6	6
		A Pretzsch	63	77	6				A Pretzsch	3	4
		P Srichaphan	77	65	1										6	M Chang	63	2
		S Sargsian	6	6											WC	T Suzuki	77	6
		A Sá	2	3					S Sargsian	5	6	4
	WC	T Suzuki	5	6	6			WC	T Suzuki	7	4	6
	12	A Ilie	7	2	4																	WC	T Suzuki	3	3
	16	R Delgado	6	6																			K Kučera	6	6
	WC	G Motomura	4	4				16	R Delgado	4	4
		K Kučera	6	4	6				K Kučera	6	6
		A Simoni	3	6	1											K Kučera	6	6
		M Lee	4	2											3	R Schüttler	2	2
		M Larsson	6	6					M Larsson	3	5
								3	R Schüttler	6	7

	First round							Second round							Third round							Quarterfinals
								5	M Kratochvil	77	1	6
		O Fukárek	6	77					O Fukárek	63	6	4
	Q	D Vacek	2	63											5	M Kratochvil	6	6
		H-T Lee	713	6											9	L Burgsmüller	3	2
		M Hantschk	611	4					H-T Lee	6	3	5
		M Llodra	63	6	2			9	L Burgsmüller	3	6	7
	9	L Burgsmüller	77	2	6																	5	M Kratochvil	6	6
	13	Á Calatrava	3	1																		2	S Schalken	3	4
		I Heuberger	6	6					I Heuberger	3	6	6
	Q	N Behr	6	6				Q	N Behr	6	4	4
	WC	T Terachi	2	1												I Heuberger	2	2
		I Labadze	77	3	5										2	S Schalken	6	6
		C Vinck	63	6	7				C Vinck	3	4
								2	S Schalken	6	6

• 2001 AIG Japan Open Tennis Championships Draw
• 2001 AIG Japan Open Tennis Championships Qualifying Draw