Jan Grudziński (3 December 1907– May/June 1940) was a submarine commander of the Polish Navy during World War II.

[1] After Poland regained independence, in late 1918 he settled with his parents in Lwów where in 1921 he entered the First Cadet Corps.

Shortly before the start of World War II, he was transferred to the submarine ORP Orzeł.

The next day, at the insistence of the Germans, Estonian military authorities boarded the ship, interned the crew, confiscated all the navigation aids and maps, and commenced dismantling all the armaments.

After exhausting the possibilities of combat, Grudziński took the decision to join United Kingdom where he arrived on 14 October.