The 20th Legislative Assembly of Ontario was in session from October 6, 1937, until June 30, 1943, just prior to the 1943 general election.
In 1938, the title "Member of Provincial Parliament", abbreviated as "MPP", was officially adopted by the members of the legislative assembly.
Hepburn resigned as Premier in October 1942, remaining party leader, and Gordon Daniel Conant became Premier.
Norman Otto Hipel served as speaker for the assembly until September 2, 1938.
James Howard Clark replaced Hipel as speaker.