From 1951 to 1979 Stefan Witkowski played eighteen times in the Polish Chess Championship's finals.

In 1954 in Łódź he shared first place with Bogdan Śliwa, but lost additional match and won the silver medal.

In 1959 Witkowski reached the Polish champion title after the victory in additional match with Józef Gromek - 4:0.

[1] Witkowski represented his country in nineteen matches and more than thirty international tournaments.

He was a multiple medalist in Polish Team Chess Championship, including eleven gold.