Editing 3rd Rock from the Sun (section)

=== Recurring characters ===
* [[David DeLuise]] as Bug Pollone, one of Dick's students
* [[Ian Lithgow]] as Leon, one of Dick's students
* [[Danielle Nicolet]] as Caryn, one of Dick's students
* [[Chris Hogan (actor)|Chris Hogan]] as Aubrey Pitman, one of Dick's students
* [[Ileen Getz]] as Dr. Judith Draper, professor at Pendelton and colleague of Mary
* [[Shay Astar]] as August Leffler, Tommy's first girlfriend (seasons 1–3, sparsely appears in seasons 3 and 4)
* [[Larisa Oleynik]] as Alissa Strudwick, Tommy's second girlfriend (seasons 4–6)
* Ron West as Dr. Vincent Strudwick, Alissa's father and rival to Dick (seasons 2–6)
* [[William Shatner]] as The [[Big Giant Head]], the aliens' boss
* [[Jan Hooks]] as Vicki Dubcek, daughter of Ms. Dubcek, Harry's on-and-off girlfriend and later the wife of the Big Giant Head and the mother of his child
* [[John Cleese]] as Dr. Liam Neesam, a professor who briefly has a relationship with Mary, and is later revealed to be an evil alien (seasons 3 and 6)
* [[Chyna]] as Janice, a muscular female police officer who is briefly Harry's girlfriend
* [[Michael Milhoan]] as Coach Strickland, a high school physical education teacher at Tommy's high school