Diamondhead Lake, Iowa

Diamondhead Lake is an unincorporated community and census-designated place in Penn Township, Guthrie County, Iowa, United States. As of the 2010 census the population was 366.

The CDP consists of a residential community that surrounds Diamondhead Lake, an artificial impoundment just south of the South Raccoon River. The community is located in the southeast corner of Guthrie County, 4 mi northwest of Dexter and 6 mi northeast of Stuart. It is 38 mi west of Des Moines.

According to the U.S. Census Bureau, the CDP has a total area of 2.0 sqkm, of which 1.6 sqkm are land and 0.4 sqkm, or 20.31%, are the waters of Diamondhead Lake.