The Wintun Glacier is a glacier situated on the eastern flank of Mount Shasta, in the U.S. state of California. It is both the third largest and third most voluminous glacier in California after the neighboring Hotlum Glacier and the Whitney Glacier. The Wintun Glacier starts on the east side of Mount Shasta's main summit, and it has the highest permanent snow and ice on the mountain, reaching above to within a few dozen feet (~8-15 m) of the true summit. The glacier flows east down a steep slope and terminates in two lobes, the longer of which extends down near .