The 1955 Ontario general election was held on June 9, 1955, to elect the 98 members of the 25th Legislative Assembly of Ontario (Members of Provincial Parliament, or "MPPs") of the Province of Ontario. The Ontario Progressive Conservative Party, led by Leslie Frost, won a fifth consecutive term in office, increasing its caucus in the legislature from 79 in the previous election to 83. The social democratic Co-operative Commonwealth Federation (CCF), led by Donald C. MacDonald, won one additional seat, for a total of three. One "PC Independent" was elected.