Lake Leavitt is a reservoir in Lassen County, California, United States. The 1,142 acres lake was created in 1889 from a natural sinkhole by Benjamin H. Leavitt. It is now part of the Honey Lake Valley irrigation system and managed by the Lassen Irrigation Company. The area is currently being remediated due to damage from cattle ranches, and is home to waterfowl, mule deer, pronghorn antelope, and other local species.