The Strait of Canso (also Gut of Canso or Canso Strait), is located in northeastern North America in the Canadian province of Nova Scotia.

It is a long thin channel (27 kilometres long, 3 kilometers wide) which separates Cape Breton Island from peninsular mainland Nova Scotia. It connects the North Atlantic Ocean to Northumberland Strait in the Gulf of St. Lawrence. The strait is extremely deep with two major communities at Port Hawkesbury on the eastern side facing Mulgrave on the western side, both ports. The strait is crossed by the Canso Causeway, although ships may pass through the Canso Canal.