John B. LaBossiere (1935–2006) was a Canadian politician who was leader of the New Brunswick New Democratic Party from 1976 to 1980. The party's first francophone leader, he was noted for making inroads into the province's Acadian community, taking the party to a then-record level of support in the 1978 provincial election. He was also an early advocate of environmentalism in the province, building his campaign on opposition to aerial spraying and to the proposed Point Lepreau Nuclear Generating Station. He resigned as leader in July 1980, following a dispute with the party's executive committee, complaining that the NDP had drifted from its socialist principles.