Robert Waldron MacQuarrie (November 24, 1926 – January 11, 2007) was a politician in Ontario, Canada.
MacQuarrie served as a government backbencher for the next four years, acting as parliamentary assistant to the Solicitor-General and Attorney-General.
In January 1985, he supported Roy McMurtry's bid to succeed Bill Davis as leader of the Progressive Conservative Party.
The Progressive Conservatives were reduced to a tenuous minority government in the 1985 provincial election, and lost power to David Peterson's Liberals.
MacQuarrie was defeated in Carleton East, losing to Liberal candidate Gilles Morin by 7,033 votes.