Mark Steven Kirk (born September 15, 1959) has been a Republican member of the United States House of Representatives since 2001, representing Illinois's 10th congressional district. Kirk is a candidate for the U.S. Senate in 2010.

Kirk was born in Champaign, Illinois, graduated from Joseph Sears School in Kenilworth, a Chicago suburb, in 1973, and New Trier East High School in 1977. He attended the Universidad Nacional Autónoma de México before graduating cum laude in history from Cornell University. Kirk received a master's degree from the London School of Economics, and a Juris Doctor degree from Georgetown University Law Center.

Kirk was commissioned in 1989 as an intelligence officer in the Naval Reserve. He is one of only two members of Congress serving as a drilling reservist one weekend a month and two weeks a year. In the Navy, Kirk served during conflicts with Haiti, Bosnia and Kosovo. He served aboard USS Normandy and USS John C Stennis. Kirk also served three tours in Panama.