John Diehl (born May 1, 1950) is an American character actor with over 150 credits to his name in film and television. He is best known for his roles as Charles Kawalsky in the 1994 film Stargate, Det. Larry Zito on the 1980s cop show Miami Vice, Assistant Chief Ben Gilroy on The Shield, and as "the Cruiser" in Stripes. His other notable roles include Pvt. Bucklin, the spokesman of the 2nd Maine mutineers in Gettysburg, Cooper in Jurassic Park III (2001), as G. Gordon Liddy in the Oliver Stone movie Nixon, the Klansman informant ("Mickey Mouse") in A Time to Kill, and as Keith, a credit card company supervisor in Mo Money. He also appeared as the spirit of Harley Earl in a series of commercials for Buick. He was born in Cincinnati, Ohio, and graduated from St. Xavier High School in 1968. For a time, he flirted with a professional boxing career, leaving Miami Vice to pursue it.

John Diehl (* 1. Mai 1950 in Cincinnati, Ohio) ist ein US-amerikanischer Schauspieler.

Bekannt wurde Diehl durch die Nebenrolle als Larry Zito neben Filmpartner Michael Talbott als Stanley Switek in Miami Vice. Seit 1980 wirkte Diehl an mehr als 120 Film- und Fernsehproduktionen mit.