Friday Mountain is a mountain located in Ulster County, New York. The mountain is part of the Catskill Mountains. Friday Mountain is flanked to the north by Cornell Mountain, and to the south by Balsam Cap.
The southeast side of Friday Mountain drains into Maltby Hollow Brook, thence into Bush Kill, the Ashokan Reservoir, Esopus Creek, the Hudson River, and into New York Bay. The northeast side of Friday Mtn. drains into Wittenberg Brook, thence into Maltby Hollow Brook. The western slopes of Friday Mtn. drain into the headwaters of the East Branch of the Neversink River, thence into the Delaware River, and into Delaware Bay.
Friday Mountain is within the Slide Mountain Wilderness of New York's Catskill State Park.