| Date | May 12, 1990 |
|---|---|
| Convention | CNE Coliseum, Toronto, Ontario |
| Resigning leader | Larry Grossman |
| Won by | Mike Harris |
| Ballots | 1 |
| Candidates | 2 |
| Entrance Fee | ? |
| Spending limit | ? |
The 1990 Ontario Progressive Conservative leadership election was a leadership convention held in May 1990 to elect a new leader for the Progressive Conservative Party of Ontario. Two candidates vied for the leadership - Mike Harris and Dianne Cunningham. Using a novel voting system used due to party funding constraints, Harris was elected over Cunningham in a single ballot by a margin of 7,175 points to 5,825 points.