ORP Sokół (Polish: Falcon) was a U-class submarine (formerly HMS Urchin) built by Vickers-Armstrong at Barrow-in-Furness.

Shortly after her trials, the boat was handed to her Polish crew, in accordance with the Anglo-Polish military alliance and amendments of 18 November 1939 and 3 December 1940.

On 28 October of that year, Sokół achieved her first victory by heavily damaging the Italian auxiliary cruiser Città di Palermo.

On 19 November of the same year, she forced the anti-submarine nets and entered the port of Navarino, where she damaged the Italian destroyer Aviere.

On 17 April while in the port of Malta, she was heavily damaged by a German air raid and was forced to return to the shipyard in Blyth to receive repairs.