Cle Elum Lake is a lake and reservoir along the course of the Cle Elum River, in Washington state USA.

At the site of the future city of Cle Elum, Washington, a Northern Pacific Railway station was named Clealum after the Kittitas name Tle-el-Lum (tlielləm), meaning "swift water", referring to the Cle Elum River.

The lake is used as a storage reservoir for the Yakima Project, an irrigation project run by the United States Bureau of Reclamation.

Although a natural lake, Cle Elum Lake's capacity and discharge is controlled by Cle Elum Dam, a 165-foot (50 m) high earthfill structure built in 1933.

As a storage reservoir, Cle Elum Lake's active capacity is 436,900 acre feet (539,000,000 m³).