Cape Spencer Light, Coastal lighthouse in Mispec, Saint John, Canada.

Cape Spencer Light stands at the eastern entrance to Saint John harbour from the Bay of Fundy, in Mispec, New Brunswick. The active aid is a conical fiberglass tower erected in 1983, replacing a skeletal tower first lit in 1971. It is owned by the Canadian Coast Guard.

New Brunswick funded a lighthouse here in 1871, and the wooden square pyramidal tower, 11 m tall with the keeper's dwelling attached, was lit on 15 June 1873 at a cost of 6,848 Canadian dollars. A road reached the station in 1877. The worn wooden tower was replaced in 1918 by a white octagonal concrete tower with a red band and red lantern room; the fog-signal building burned on 29 November 1927 and was rebuilt the next year. A skeletal tower took over in 1971, and the present conical fiberglass tower followed in 1983.

The station's name comes from Cape Spencer, the headland at the eastern entrance to Saint John's harbour from the Bay of Fundy. The site has been staffed and rebuilt repeatedly since 1873, and the light is now owned by the Canadian Coast Guard. The 1877 supply road made the remote point easier to reach.

The lighthouse grounds can be reached via Red Head Road from Market Square in Saint John. The tower itself is closed to visitors, but the exterior area can be viewed.

The 1873 tower was a square wooden pyramid 11 metres tall with the keeper's dwelling attached, and the whole station cost 6,848 Canadian dollars. A road reached the site in 1877, and electricity arrived in 1913. The fog-signal building burned down on 29 November 1927 and was rebuilt the next year.