Autovía A-55
Autovía del Atlántico
Route information
Length	32 km (20 mi)
Major junctions
From	Vigo
To	Portugal–Spain border at Tui
Location
Country	Spain
Highway system
Highways in Spain Autopistas and autovías National Roads

The Autovía A-55 (also known as Autovía del Atlántico) is an autovía in Galicia (Spain). It is 32 km (20 miles) long and runs from the centre of Vigo to the Portugal–Spain border, on the Minho River at Tui, where it connects to the A3 motorway (Portugal).

The A-55 runs parallel to the Autopista AP-9 for much of its length, and also connects with the Autovía A-52 at the town of O Porriño. Between Vigo and O Porriño, the autovía is an upgrade of the N-120 road, and between O Porriño and the Portuguese border it is an upgrade of the N-550. For the final 5 km (3 miles) of its length, from the end of the AP-9 north of Tui to the Portuguese border and the A3 autoestrada, the A-55 forms part of European route E01.