Allison Glacier (53°04′S73°24′E) is an ice stream on the west side of Heard Island in the southern Indian Ocean. Allison Glacier flows from Big Ben massif down to the sea to the south of Cape Gazert. To the north of Allison Glacier is Vahsel Glacier, whose terminus is at South West Bay, between Erratic Point and Cape Gazert. Immediately to the north of Vahsel Glacier is Schmidt Glacier, whose terminus is located between Mount Drygalski and North West Cornice.