ORP Wilk was the lead boat of her class of mine-laying submarines of the Polish Navy. The ship saw service in the Polish Navy from 1931 to 1951. Her name meant "Wolf" in Polish.
Wilk was laid down in 1927 at Chantiers et Ateliers Augustin Normand shipyard at Le Havre in France. Launched on April 12, 1929, she was commissioned into the Polish Navy on 31 October 1931.
When World War II began on September 1, 1939, Wilk, commanded by Captain Boguslaw Krawczyk, took part in the Worek Plan for the defence of the Polish coast, operating in Gdańsk Bay. On September 2 she spotted a destroyer Erich Steinbrinck, but could not attack it, because she fell herself under attack of minesweepers (the German report on firing a torpedo at Steinbrinck is not confirmed by the Polish). On September 3 she deployed her mines as planned. On September 4 and 5 the Wilk was under continuous depth charge attacks and had to lay on the sea bottom during daytime, suffering minor damage. During next days, attempts at attacking enemy shipping were unsuccessful. Then she left the Polish coast, successfully passing the Danish straits (Øresund) on September 14/15, escaping from the Baltic Sea and arriving in Great Britain on September 20. Only ORP Orzeł managed to accomplish the same feat later; the other three Polish submarines were interned in neutral Sweden.
On December 7, 1939 one of the mines laid by the submarine in September sank a German fishing boat MFK Pil 55 Heimat (13 GRT) at position 54°37′05″N 19°47′00″E.
On June 20, 1940 at 0.25 am, the ORP Wilk rammed an unidentified object at position 56°54′N 03°30′E. There was a long dispute upon this incident. The 2nd in command Sub.Lt. Bolesław Romanowski claimed in his memoires "Torpeda w celu", that it was a German U-boot. Supporters of this version suggested, that it might have been U-22, lost some time earlier. Some suggested, that it might have been an Allied Dutch submarine O13, also lost at sea around that time. However, according to newest analysis of Wilk's damages and all reports, the object was most likely a buoy, since both Wilk's propellers got damaged, while a rudder and rudder's connector below them, was intact, which was unlikely in case of ramming a submarine.
She undertook nine patrols from the British bases, without success. The last patrol was between 8 and 20 January 1941, then the submarine was assigned to training duties. Due to her poor mechanical shape, ORP Wilk was decommissioned as a reserve submarine on April 2, 1942.
On 28 September 1946 ORP Wilk was given under the British control by the Polish Government in Exile. The submarine remained laid up at Harwich. Because of her poor condition, only in October 1952 she was towed to Poland. She was declared unfit to service, decommissioned from the Polish Navy, and scrapped in 1954.
A second ORP Wilk, a Foxtrot class submarine, served in the Polish Navy from 1987 to 2003.