German submarine U-1171 was a Type VIIC/41 U-boat of Nazi Germany's Kriegsmarine during World War II.

She was launched on 23 November 1943, and commissioned under the command of Oberleutnant zur See Otto Heinrich Nachtigall on 22 March 1944.

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 SSW GU 343/38-8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged.

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).

U-1171 would be spared, for a time, becoming a British N-class submarine, N19, used for testing and then in April 1949, broken up at Sunderland.