Mark Ridley-Thomas (born November 6, 1954) is a member of the Los Angeles County Board of Supervisors for District 2. He served as a California State Senator, representing the 26th district from 2006 to 2008 and was a California State Assemblyman representing the 48th district from 2002 until 2006. He was Chairman of the Assembly Democratic Caucus. Before his six years in the Legislature, he was on the Los Angeles City Council from 1991 to 2002.