Gary Lockwood (born February 21, 1937) is an American actor born John Gary Yusolfsky.

Lockwood is probably best known for his role as astronaut Dr. Frank Poole in 2001: A Space Odyssey (1968).

Lockwood's notable television work includes playing Lt. Commander Gary Mitchell in "Where No Man Has Gone Before", the first episode of Star Trek. He also co-starred with his then-wife Stefanie Powers in an episode of Love, American Style in which he got his mouth stuck on a doorknob.