Kurt Russell as MacReady

Keith David as Childs

Wilford Brimley as Blair

T.K. Carter as Nauls

David Clennon as Palmer

Richard Dysart as Dr. Copper

Charles Hallahan as Norris

Peter Maloney as Bennings

Richard Masur as Clark

Donald Moffat as Garry

Joel Polis as Fuchs

Thomas G. Waites as Windows

Norbert Weisser as Norwegian

Larry Franco as Norwegian Passenger with Rifle

Nate Irwin as Helicopter Pilot

William Zeman as Pilot

Jed as The Thing (uncredited)

John Carpenter as Norwegian (video footage) (uncredited)

Adrienne Barbeau as Computer (voice) (uncredited)