The district includes parts of Riverside County, including Jurupa Valley, Riverside, Moreno Valley, and Perris.

The 39th district takes in the cities of Moreno Valley, Jurupa Valley, Perris, and Riverside, as well as the census-designated places Mead Valley, Home Gardens, Highgrove, March Air Reserve Base, Good Hope, and Meadowbrook 1972 • 1974 • 1976 • 1978 • 1980 • 1982 • 1984 • 1986 • 1988 • 1990 • 1992 • 1994 • 1996 • 1998 • 2000 • 2002 • 2004 • 2006 • 2008 • 2010 • 2012 • 2014 • 2016 • 2018 • 2020 • 2022 In January 2018, Republican incumbent Ed Royce announced his retirement.

[30] Royce's retirement created great uncertainty and interest in this election, due to the possibility of two candidates of the same political party winning California's jungle primary.

[31][32] The primary election resulted in two candidates of different parties, with Republican Assemblywoman Young Kim and Democrat Gil Cisneros coming in first and second place respectively.

[34] The 39th congressional district was originally one of five reapportioned to California after the 1970 United States census.