German submarine U-1055 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II.

The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged.

[2] When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph).

In two patrols she sank four merchant ships, for a total of 19,413 gross register tons (GRT).

[4] Other accounts (Flypast April 2021) state that U-1055 was sunk west of Brest shortly after 18:00 on 30 April by an anti-submarine PBY-5 Catalina commanded by Lt. F. G. Lake of 19 Group, but this attack actually resulted in the sinking of U-1107.