The Allalin Glacier () is a long glacier (2005) situated in the Pennine Alps near the Allalinhorn in the canton of Valais in Switzerland. In 1973 it had an area of . The glacier is bordered on the west by the Allalinhorn, Rimpfischhorn and Strahlhorn. It is not to be confused with the Fee Glacier which lies on the northern flank of Allalinhorn.