Marguerite Pitre (5 September 1908 – 9 January 1953), born Marguerite Ruest, also known as Marguerite Ruest-Pitre, was a Canadian conspirator in a mass murder carried out when Albert Guay bombed an airliner, killing all 23 people on the plane.
The 13th and last woman to be hanged in Canada, she was executed on 9 January 1953 in Montreal, Quebec.