Dungeon Peak is a mountain summit located in the Cascade Range, in Kittitas County of Washington state. It is situated northeast of Hyak, Washington, near the north end of Keechelus Lake, within the Alpine Lakes Wilderness, on land managed by Wenatchee National Forest. Its nearest higher neighbor is Rampart Ridge, to the north-northeast. The mountain is set above the Gold Creek valley on the western side, and Lake Lillian on the eastern side. Precipitation runoff from the peak drains into tributaries of the Yakima River.