Republican Travis Allen, a member of the California State Assembly, Democrat Antonio Villaraigosa, the former Mayor of Los Angeles, Democrat Delaine Eastin, the former State Superintendent of Public Instruction and Republican John Cox, a business executive, all attended the forum.
Lt. Gov. Gavin Newsom declined to participate.
All four candidates made their positions clear on a number of issues facing California, from homelessness and housing to the state of education.
Watch the debate below: