Roy Thinnes (born 1938) is an American actor. He has appeared mostly on television, but also in some films.
- General Hospital (serial) segments 1, 2, & 3 with Manhunt in Space, The Beatniks, and Crash of Moons (Experiments #413, 415, & 417 respectively) - as Dr. Phil Brewer
- Code Name: Diamond Head (Experiment #608) - as Johnny Paul
- Roy Thinnes is one of the few identifiable actors to have appeared in both a short and a feature used on Mystery Science Theater 3000 (see also Chick Chandler & Lon Chaney Jr.) though all of Mr. Thinnes appearances were in material originally produced for television.
- Thinnes was one of the actors name-checked in the Quinn-Martin Nature Preserve sketch during Experiment #520 Radar Secret Service, where it was said he could be found picking nits off of Buddy Ebsen (though Crow later realized that the idea was implausible).