Byam Martin Island (BEI-uhm) is one of the uninhabited members of the Queen Elizabeth Islands in the Canadian arctic islands located on the northern side of the Viscount Melville Sound in the territory of Nunavut. It is separated from the eastern coast of Melville Island, 27 km to the west, by the Byam Martin Channel; and from Bathurst Island, 35 km to the northeast, by the Austin Channel. Byam Martin Island is 46 km long, 37 km wide, and measures 1150 km2 in area. The island was named after Sir Thomas Byam Martin by Sir William Edward Parry in August 1819 during his first expedition to discover the Northwest Passage.