All 96 actors in both 3rd Rock from the Sun and Seinfeld
96 actors have appeared in both 3rd Rock from the Sun and Seinfeld, across 319 episodes. The most-credited is Wayne Knight, Officer Don Orville in 3rd Rock from the Sun and Newman in Seinfeld.
| Actor | In 3rd Rock from the Sun | In Seinfeld | Eps | Eps |
|---|---|---|---|---|
| Wayne Knight | Officer Don Orville | Newman | 8 | 49 |
| Ileen Getz | Dr. Judith Draper | Organizer | 32 | 1 |
| Ron West | Dr. Vincent Strudwick | Dr. Strugatz | 16 | 1 |
| Richard Fancy | Judge DeBelko | Mr. Lippman, Mr. Breckman | 2 | 10 |
| Michael Milhoan | Coach Strickland | Security Guard | 5 | 1 |
| Richard McGonagle | Dr. Howard | Mr. Star | 5 | 1 |
| John D'Aquino | Mr. Randell | Todd Gack | 4 | 1 |
| Victor Raider-Wexler | Janitor | Doctor | 1 | 4 |
| Ana Gasteyer | Ana Gasteyer, Dr. Brand | Woman | 3 | 1 |
| Carlos Jacott | Dr. Schulman | Ramon | 2 | 2 |
| Pat Finn | Chaz Montana, Paul | Joe Mayo | 3 | 1 |
| Sam Lloyd | Eddie | Ricky | 2 | 2 |
| Brenda Strong | Mrs. Frost | Sue Ellen | 2 | 4 |
| Bryan Cranston | Neil | Tim Whatley | 1 | 5 |
| Michael McShane | Phil | Franklin Delano Romanowski | 1 | 2 |
| Phil Hartman | Phillip, Randy | Man on Phone | 2 | 1 |
| Chip Chinery | Guy, Janitor, Maintenance Guy | Co-Worker #1 | 4 | 1 |
| Amy Hill | Rita | Kim | 1 | 1 |
| Bob Odenkirk | Gary | Ben | 1 | 1 |
| Everett Greenbaum | Norman | McMaines | 1 | 1 |
| Katherine LaNasa | Kate | Cathy | 1 | 1 |
| Megan Mullally | Renata Albright | Betsy | 1 | 1 |
| Peter Krause | Peter Connelly | Tim | 1 | 1 |
| Bruce Ed Morrow | Father Rice | Father Jessup | 4 | 1 |
| Lane Davies | Chancellor Duncan | MacKenzie | 2 | 1 |
| Mark Christopher Lawrence | Bartender | Boss, Skycap | 1 | 2 |
| Maurice Godin | Marty | Misha | 2 | 1 |
| Philip Baker Hall | President Dewey | Lt. Bookman | 1 | 2 |
| Lawrence Mandley | Carlos | Larry, Larry the Cook, Manager | 1 | 6 |
| David Brisbin | Professor Brandon | Client | 1 | 1 |
| David Dunard | Mechanic | Guard, Leader, Security Guard | 1 | 3 |
| Eugene Elman | Stan | Buddy | 1 | 1 |
| Kevin Ruf | New Father, T.V. Reporter #2 | Security Guard | 2 | 1 |
| Larry Miller | Garvin | Doorman | 1 | 1 |
| Meagen Fay | Annabet | Mrs. Burns | 1 | 1 |
| Rachel Davies | Flora | Saleswoman | 1 | 1 |
| Rif Hutton | Bookstore Guy | Salesman | 1 | 1 |
| Suanne Spoke | Bibi | Customer | 1 | 1 |
| Terry Rhoads | Bill, Salesman | Father | 2 | 1 |
| Tim Bagley | Frank | Manager | 1 | 1 |
| Julie Claire | Jenny | Receptionist, Waitress | 1 | 4 |
| Bart McCarthy | Grouch, Hamlet | Cab Driver | 2 | 1 |
| Carol Mansell | Mrs. Smith | Mother | 1 | 2 |
| Fred Pinkard | Louis | Newstand Boy, Old Man | 1 | 2 |
| Henry Woronicz | Mr. St. Clair | Father Curtis | 1 | 2 |
| Patrick Kerr | Irving | La Forge - Clerk | 2 | 1 |
| Rick Hall | Limo Driver | Vet | 1 | 2 |
| Sonya Eddy | Ticket Taker | Rebecca DeMornay | 1 | 2 |
| Christopher Carroll | Justice of the Peace | Maitre'd | 1 | 1 |
| Danny Strong | Aramis | Vincent | 1 | 1 |
| Joel McCrary | George | Don | 1 | 1 |
| Lauren Graham | Laurie Harris | Valerie | 1 | 1 |
| Louan Gideon | Saleswoman | Mrs. Hamilton | 1 | 1 |
| Raye Birk | Jeweler | Mr. Pless | 1 | 1 |
| Eddie Allen | Dr. Bankson | Doctor | 2 | 1 |
| Dee Freeman | Waitress, DMV Clerk | Service Assistant | 3 | 1 |
| Darlene Kardon | Old Woman | Mrs. Lupchek | 1 | 1 |
| Diana Castle | Saleswoman | Mrs. Zanfino | 1 | 2 |
| Elayn J. Taylor | Teacher #1 | Book Fan | 1 | 1 |
| Jeanine Jackson | Claire | Roxanne | 1 | 1 |
| Jerry Hauck | Frank | Tim | 1 | 1 |
| Linda Kash | Margie | Gwen | 1 | 1 |
| Maria Cina | Onya | Saleswoman | 1 | 1 |
| Nancy Lenehan | Mrs. St. Clair | Volunteer | 1 | 1 |
| Richard Livingston | Dr. Hallstrom | Bill | 1 | 1 |
| John Hillner | Steve | Greeny | 1 | 1 |
| Kathryn Joosten | Cafeterial Lady | Betsy | 1 | 1 |
| Katie Layman | Muriel | Cynthia | 1 | 1 |
| Scott Klace | Mark | Guard | 1 | 1 |
| Shireen Crutchfield | Kirsta | Model #2 | 1 | 1 |
| Susan Ilene Johnson | Linda | Nurse | 1 | 1 |
| Theresa Mulligan Rosenthal | Triple A Lady | Woman | 1 | 1 |
| Tom Towles | Dale | Tough Guy | 1 | 1 |
| Bill Lee Brown | Customer #1 | Partygoer | 1 | 1 |
| David Chandler | Mr. Wexler | Brian | 1 | 1 |
| Denise Poirier | Judy | Arlene | 1 | 1 |
| Elsa Raven | Aunt Florence | Mom | 1 | 1 |
| J. Patrick McCormack | Victor's Dad | Leland | 1 | 1 |
| Jack Hallett | Jury Foreman | Alan | 1 | 1 |
| Jay Leno | Jay Leno | Jay Leno | 1 | 1 |
| Ken Thorley | Artie | Car Salesman | 1 | 1 |
| Patricia Bethune | Teacher | Walker #3 | 1 | 1 |
| Richard Roat | Dr. Byron | Dr. Berg | 1 | 1 |
| Dublin James | Vinny | Maurice | 1 | 1 |
| Layne Beamer | Jace | Father | 1 | 1 |
| Peggy Mannix | Charity Women | Woman | 1 | 1 |
| Ray Proscia | Mugger | Bobby | 1 | 1 |
| Susan Leslie | Kissing Woman | Nurse | 1 | 1 |
| Van Epperson | Bill | Passerby | 1 | 1 |
| Mailon Rivera | Campus Cop | Cop #1 | 1 | 1 |
| Marvin Braverman | Izzy | Cop, Poker Player #1 | 1 | 2 |
| Sid Newman | Phelps | Old Man | 1 | 1 |
| Audrey Kissel | Angela | Tara | 1 | 1 |
| Sean Moran | Ernie | Man | 1 | 1 |
| Kyle Colerider-Krugh | Elroy | Phone Guy #2 | 1 | 1 |
| Mimi Cozzens | Hamilton | Mrs. Canterman | 1 | 1 |
← 3rd Rock from the Sun × Seinfeld
Cast data from TVmaze, licensed CC BY-SA 4.0.