Ross MacKenzie (born 18 July 1946) is a Canadian sprinter. He competed in the men's 400 metres at the 1968 Summer Olympics. He finished second in the 1967 Pan American Games 4 × 400 metres relay (with Brian MacLaren, Bill Crothers, and Robert McLaren). MacKenzie also finished fifth in the 1967 Pan American Games 400 metres. He won a silver medal in the 1966 British Empire and Commonwealth Games 4 x 440 yards relay with Don Domansky, Brian MacLaren and Bill Crothers.