Canadian Mineworkers Union

The Canadian Mineworkers Union (CMU) was a Canadian trade union of coal miners based in Cape Breton Island, Nova Scotia. Although it never won an election or legally represented workers, it was part of an important movement among Canadian unions in the 1980s to break away from their international American counterparts.

The CMU is distinguished from a local, independent union of the same name which existed at the Clinton Creek mine in the Yukon. This local union, which existed from late 1972 into 1978, was formed when miners decertified the United Steel Workers of America and formed their own union.