The 1937 Ontario general election was held on October 6, 1937, to elect the 90 Members of the 20th Legislative Assembly of Ontario ("MLAs"). It was the 20th general election held in the province of Ontario.
The Ontario Liberal Party, led by Mitchell Hepburn, was re-elected for a second term in government, with a slightly reduced majority in the Legislature.
The Ontario Conservative Party, led by William Earl Rowe, was able to win six additional seats, and continued to form the official opposition.
Meanwhile, the fledgling democratic socialist Co-operative Commonwealth Federation (CCF) ran 37 candidates out of a possible 90, led by party president John Mitchell running in Waterloo South, who also campaigned throughout the province on the party's behalf. The election, however, resulted in a modest decline in popular vote and the loss of the party's sole MLA, Sam Lawrence in Hamilton East.
Incumbent MLA Farquhar Oliver was the last remaining United Farmers of Ontario MLA and ran as the party's sole candidate in the election. In practice, however, he had been a supporter of the Liberal government and would join Hepburn's cabinet in 1940, formally joining the Liberal Party.
In 1938, MLAs voted to adopt the title "Member of Provincial Parliament", and became known as "MPPs".
This Ontario election was the last to date in which the winning party (together with effective support from the Liberal-Progressives and UFO, against which they did not field opposing candidates) has won an absolute majority of the popular vote.
|- ! colspan=2 rowspan=2 | Political party ! rowspan=2 | Party leader ! colspan=5 | MPPs ! colspan=3 | Votes |- ! Candidates !1934 !<small>Dissol.</small> !1937 !ñ !# !% ! ñ (pp)
|style="text-align:left;"|Mitchell Hepburn | 85 || 64 || 66 || 62 || 2 || 769,747 || 48.99 || 2.43
|style="text-align:left;"|William Earl Rowe | 89 || 17 || 17 || 23 || 6 || 619,610 || 39.44 || 0.34
|style="text-align:left;"| | 4 || 5 || 4 || 3 || 2 || 24,752 || 1.58 || 1.31
|style="text-align:left;"| | 8 || – || 1 || 1 || 1 || 20,776 || 1.32 || 0.53
|style="text-align:left;"|Farquhar Oliver | 1 || 1 || 1 || 1 || || 7,296 || 0.46 || 0.09
|style="text-align:left;"|John Mitchell | 37 || 1 || 1 || – || 1 || 77,833 || 4.95 || rowspan="2"| 1.66
|style="text-align:left;"|CCF-Labour |style="text-align:left;"| | 2 || – || – || – || – || 5,746 || 0.37
|style="text-align:left;"| | 7 || 1 || 1 || – || 1 || 4,039 || 0.26 || 0.96
|style="text-align:left;"| | – || 1 || – || – || 1 || colspan="3"|Did not campaign
|style="text-align:left;"| | 6 || – || – || – || – || 14,675 || 0.93 || 0.89
|style="text-align:left;"| | 7 || – || – || – || – || 11,807 || 0.75 || 0.74
|style="text-align:left;"| | 5 || – || – || – || – || 8,270 || 0.53 || 0.50
|style="text-align:left;"| | 1 || – || – || – || – || 3,343 || 0.21 || rowspan="2"| 0.37%
|style="text-align:left;"| | 1 || – || – || – || – || 408 || 0.03
|style="text-align:left;"| | 11 || – || – || – || – || 2,199 || 0.14 || 0.04
|style="text-align:left;"| | 1 || – || – || – || – || 538 || 0.03 || New
|style="text-align:left;"| | 1 || – || – || – || – || 94 || 0.01 || 0.02 |-style="background:#E9E9E9;" |colspan="3" style="text-align:left;"|Total |266 |90 |90 |90 | |1,571,133 |100.00% | |- |colspan="8" style="text-align:left;"|Blank and invalid ballots |align="right"|17,271 |style="background:#E9E9E9;" colspan="2"| |-style="background:#E9E9E9;" |colspan="8" style="text-align:left;"|Registered voters / turnout |2,238,230 |71.29% |2.32
There were 17 seats that changed allegiance in the election.
Liberal to Conservative
Conservative to Liberal
Liberal-Progressive to Liberal
CCF to Liberal
Liberal-Labour to Liberal
Independent to Independent-Liberal