Curnoe was a founding member of the Nihilist Spasm Band. In London, Ontario he founded Region magazine in 1961, Region Gallery in 1962, and co-founded the Forest City Gallery, an artist-run centre in 1973. He co-founded CARFAC with Jack Chambers in 1968.
Curnoe was an avid cyclist, and bicycles were a frequent subject of his work. While on a club ride in 1992, a distracted driver of a pickup truck failed to see the group of riders and plowed into them. Curnoe was killed and several others were seriously injured.