Mono County is a county located in the east central portion of the U.S. state of California, to the east of the Sierra Nevada between Yosemite National Park and Nevada. As of 2000 the population was 12,853. The county seat is Bridgeport.

The only incorporated city in the county is Mammoth Lakes, which is located at the foot of Mammoth Mountain. Other locations, such as June Lake, are also famous as skiing and fishing resorts. Located in the middle of the county is Mono Lake, a vital habitat for millions of migratory and nesting birds. The lake is located in a wild natural setting, with pinnacles of tufa arising out of the salty and alkaline lake. Also located in Mono County is Bodie, the official state gold rush ghost town, which is now a California State Historic Park.