2003 Progressive Conservative leadership election

(64.8%)** (45.0%) (39.7%) (41.1%) (35.2%) (30.4%) (18.2%) (18.2%) (24.6%) (24.1%) (24.3%) (18.0%) (16.4%) party = Progressive Conservative| colour = | year = 2003| logo = | date = May 31, 2003| location = Metro Toronto Convention Centre, Toronto, Ontario | winner = Peter MacKay | replaces = Joe Clark | numcands = 5| ballots = 4| entryfee = C$| spendcap = None|

The 2003 Progressive Conservative leadership election was held on May 31, 2003, to elect a leader of the Progressive Conservative Party of Canada. Peter MacKay was elected as leader to replace former Prime Minister Joe Clark, who then retired as party leader. In the end, five candidates emerged as challengers for the leadership by the convention date. Two other candidates had participated in the race but both withdrew as contestants before the vote. Quebec Member of Parliament (MP) André Bachand withdrew his candidacy from the race due to financial concerns and backed Peter MacKay. Former Cabinet Minister and Quebec MP Heward Grafftey also withdrew his candidacy from the race due to health concerns and backed David Orchard.

The results of the race produced immediate controversy when it emerged that winner Mackay had signed an agreement with David Orchard in order to get elected. This deal promised the party would review the Canadian-American Free Trade Agreement, and that it would not cooperate or merge with the Canadian Alliance. This controversy continued when MacKay ignored the agreement, and signed an agreement to merge his party with the Canadian Alliance to form the new Conservative Party of Canada. The merger was approved by party members in December 2003. After the merger was approved, Brison announced that he was defecting to the Liberals.