Antelope Flat Reservoir, Mountain reservoir in Ochoco National Forest, Oregon, US.

Antelope Flat Reservoir is a 170-acre impoundment in the southern Maury Mountains of Crook County, Oregon, formed by a 33-foot earth-fill dam across Bear Creek. Its western part lies within Ochoco National Forest. The lake sits at 4,984 feet elevation, has a maximum depth of 28 feet and an average depth of 11 feet, and stores almost 2,000 acre-feet for irrigation.

The reservoir was built in the mid-1900s as part of regional water management projects to support irrigation agriculture in the area. The dam created this lake by blocking Bear Creek, helping to store water for dry seasons when farmers needed reliable supply.

The reservoir lies in the southern Maury Mountains, and its western arm falls inside the Ochoco National Forest. The name comes from Antelope Flat, the open bench of land recorded beside the water. The lake is a stocked fishing spot, and the boat ramp at the western end is the main access point for anglers.

The western side of the lake has a boat launch area and a campground with roughly 24 spots positioned uphill from the water. Water levels change significantly depending on the season, so plan your visit knowing that access conditions and water activities may vary throughout the year.

The reservoir's average depth is only 11 feet (3.4 m) against a maximum of 28 feet (8.5 m), and it is often not filled to capacity late in the irrigation season. The western end lies inside the Ochoco National Forest, while the rest sits in Crook County outside it. Drake Butte rises 1,901 m, about 4.2 km south of the water.