Port Union is a historical community overlooking Trinity Bay and Catalina Harbour, on the east side of the Bonavista Peninsula, Newfoundland and Labrador, Canada.
William Coaker founded the town as the base for the Fishermen's Protective Union in 1916. It was the base for the publication of the Fishermen's Advocate journal.
In 1999, the original part of the town and the nearby hydroelectric plant were designated a National Historic Site of Canada.
In 2005, Port Union was amalgamated with Catalina and Melrose to form the town of Trinity Bay North.
In 2012, the local fish plant closed.