William Joseph Poupore (April 29, 1846 – August 17, 1918) was a Canadian politician.

Born in Allumette Island, Canada East, the son of William Poupore and Susan McAdams, Poupore was educated on Allumette Island and at Ottawa College where he studied law for two years.

He was elected to the Legislative Assembly of Quebec for the electoral district of Pontiac in a by-election held in 1882.

Poupore died in Westmount at the age of 72 and was buried in the Notre Dame des Neiges Cemetery.

This article about a Quebec Member of Parliament from the Conservative Party of Canada (1867–1942) is a stub.