German submarine U-1222 was a Type IXC/40 U-boat built for Nazi Germany's Kriegsmarine during World War II.

The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of 4,400 metric horsepower (3,240 kW; 4,340 shp) for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of 1,000 shaft horsepower (1,010 PS; 750 kW) for use while submerged.

About three months later she was commissioned into service on 1 September 1943 under the command of Kapitänleutnant Heinz Bielfeld (Crew 34) in the 4th U-boat Flotilla.

After work-up for deployment, U-1222 transferred to the 10th U-boat Flotilla and left Kiel for the West Atlantic on 13 April 1944 for her first and only patrol.

Returning from patrol, U-1222 was charging her batteries while submerged, when her snorkel was spotted by a British aircraft, Sunderland 'P' of No.