Jakob Frederik "Sjaak" Köhler (2 October 1902 – 19 June 1970) was a Dutch water polo player and swimmer.

He finished in seventh and fifth place with the Dutch water polo team at the 1924 and 1928 Olympics;[1] at both Games he played three matches and scored four and two goals, respectively.

In 1924 he also competed in two freestyle swimming events (400 m and 4×200 m relay), but failed to reach the finals.

His cousin Koos played water polo alongside Sjaak at the 1928 Olympics.

This biographical article related to a Dutch swimmer is a stub.