William "Billy" McKenzie Barlow (1871 – February 14, 1963) was a Canadian amateur ice hockey player in the late 1800s. He played for the Montreal Hockey Club, champions of the Amateur Hockey Association of Canada (AHAC) from 1888 to 1897, and first winners of the Stanley Cup in 1893. Barlow is credited with scoring the first Stanley Cup-winning goal in history in the final playoff match of 1894.