All 127 actors in both NCIS and Seinfeld
127 actors have appeared in both NCIS and Seinfeld, across 688 episodes. The most-credited is Robert Wagner, Anthony DiNozzo Sr. in NCIS and Dr. Abbott in Seinfeld.
| Actor | In NCIS | In Seinfeld | Eps | Eps |
|---|---|---|---|---|
| Robert Wagner | Anthony DiNozzo Sr. | Dr. Abbott | 13 | 1 |
| Richard Fancy | Leonard Weiss | Mr. Lippman, Mr. Breckman | 1 | 10 |
| Melinda McGraw | Diane Sterling | Angela | 6 | 1 |
| Phil Morris | Navy Capt. Paul Martino | Jackie Chiles | 1 | 6 |
| Rena Sofer | Margaret Allison Hart | Mary Ann | 6 | 1 |
| Elayn J. Taylor | Odette Malone | Book Fan | 5 | 1 |
| Lauren Bowles | Mary Wiles, Nance Freeman | Waitress, Blonde Longhaired Woman, Waitress #1 | 2 | 9 |
| Ping Wu | Peter Liu | Ping | 1 | 4 |
| Victor Raider-Wexler | Patrick Carmody | Doctor | 1 | 4 |
| Brian George | Dr. Ameen Temani | Babu Bhatt | 1 | 3 |
| Christine Dunford | Jeri Fleckman | Leslie, Saleswoman | 1 | 2 |
| Rif Hutton | Marine General Phillip Braxton | Salesman | 2 | 1 |
| Tim DeKay | Senator Patrick Kiley | Kevin | 1 | 2 |
| Tom Wright | Warden Sam Kelleher | Morgan, Executive | 1 | 4 |
| Adam Wylie | Darin Spotnitz | The Kid | 1 | 1 |
| Elizabeth Morehead | Medical Corpsman | Noel | 1 | 1 |
| Gina Hecht | Christine Newhall | Dana Foley | 1 | 3 |
| Kari Coleman | Maggie Scott | Allison | 1 | 3 |
| Julie Claire | Lois Heller | Receptionist, Waitress | 1 | 4 |
| French Stewart | Paul Triff | Manager | 2 | 1 |
| Jack McGee | Det. Floyd, Richard "Rick" Jordan | Ralph | 2 | 1 |
| Larry Miller | Ed Slater | Doorman | 2 | 1 |
| Matt McCoy | Senator Thomas Bransfield | Lloyd Braun | 1 | 2 |
| Susan Walters | Marcy Brooks | Dolores, Mystery Woman | 1 | 2 |
| Bruce Davison | Lester Burm | Wyck | 1 | 3 |
| Anthony Starke | Derrick Choyce | Jimmy | 1 | 1 |
| Gina Gallego | Judge Monica Fernandez | Gina | 1 | 1 |
| Jessica Tuck | Gloria Caplinger | Bonnie | 1 | 1 |
| John D'Aquino | Ken Ashmore | Todd Gack | 1 | 1 |
| JoNell Kennedy | Navy Commander Lisa Cleveland | Secretary | 1 | 1 |
| Judy Kain | Gladys Stone | Lorraine | 1 | 1 |
| Louis Mustillo | Emilio "Freckles" Zucado | Phil | 1 | 1 |
| Mark Harelik | Ron Levinson | Milos | 1 | 1 |
| Melora Walters | Susan Lowe | Jane | 1 | 1 |
| Michael Des Barres | Del Finney | Restaurateur | 1 | 1 |
| Peter Murnik | Admiral Michael Caplinger | Lt. Martel | 1 | 2 |
| Rick Overton | Elmer Barlow | The Drake | 1 | 2 |
| Susan Diol | Doris Sawyer, Dr. Leslie Burke | Audrey | 2 | 1 |
| Tim De Zarn | David Runion | Salesman | 1 | 1 |
| Michael McShane | Dr. Matthew Heller | Franklin Delano Romanowski | 1 | 2 |
| Rick Hall | Larry Lawrence | Vet | 1 | 2 |
| Brian McNamara | Noah Sykes | James | 1 | 1 |
| Daniel Zacapa | Detective Martin Alonzo | Power Guy | 1 | 1 |
| Dave Florek | Virgil McKeever | Harry | 1 | 1 |
| Don McManus | Mark Stafford | Duncan | 1 | 1 |
| Edie McClurg | Ruth Potts | Mrs. Oliver | 1 | 1 |
| Eric Allan Kramer | Phillip Ekkerly | Biker | 1 | 1 |
| Erick Avari | Col. Dan McClafferty | Cabbie | 1 | 1 |
| Frantz Turner | Abe Mathison | Salesman | 1 | 1 |
| Harry Van Gorkum | Alton Brinkman | Craig | 1 | 1 |
| Jeremiah Birkett | Dean Neil Pattterson | Jean-Paul | 1 | 1 |
| John Bishop | Army Surplus Store Owner | Ticket Man | 1 | 1 |
| John Kapelos | Vice Principal Vic Castor | Barry | 1 | 1 |
| John Posey | Lance Simmons | Dr. Fein | 1 | 1 |
| Marguerite MacIntyre | Commander Lauren Tyler | Karen | 1 | 1 |
| Markus Flanagan | Navy Commander Mike Taffet | Charles | 1 | 1 |
| Molly Hagan | Audrey Vetter | Sister Roberta | 1 | 1 |
| Oliver Muirhead | Jay Danorth | Lubeck | 1 | 1 |
| Peggy Stewart | Elderly Lady | Aunt May | 1 | 1 |
| Rebecca McFarland | Det. Rapp | Anna | 1 | 1 |
| Richard Burgi | Randall Hammond | Ben | 1 | 1 |
| Shannon Cochran | Mallory Linn | Sheila | 1 | 1 |
| Shashawnee Hall | Police Chief Walen | Usher | 1 | 1 |
| Shireen Crutchfield | Jane Woods | Model #2 | 1 | 1 |
| Stephen Lee | Chuck Bayliss | Conrad | 1 | 1 |
| Steve Eastin | Frank Smith | Cop #1 | 1 | 1 |
| Van Epperson | Pop | Passerby | 1 | 1 |
| Virginia Watson | Nurse Ruth Corruthers | Nun | 1 | 1 |
| Todd Bosley | FBI Tech | Joey | 1 | 2 |
| Angelo Tiffe | Jed Hamilton | Delivery Man | 1 | 1 |
| Christopher Darga | Skip Harris | Driver | 1 | 1 |
| Ed O'Ross | Dao Huang | Cop #2, Det. Blake | 1 | 2 |
| Greg Collins | Police Officer Metro PD | Policeman | 1 | 1 |
| Jesse D. Goins | Jeffrey Wilson | Cop | 1 | 1 |
| Lou DiMaggio | Nestor Carbone | Stagehand | 1 | 1 |
| Mark L. Taylor | Dr. Harvey Kimball | Michael | 1 | 1 |
| Miguel Pérez | Federal Marshal Van Driver | Luis | 1 | 1 |
| Nancy Linehan Charles | Ruthann Harrison | Woman Exec. | 1 | 1 |
| Patricia Bethune | Paulette Quinn | Walker #3 | 1 | 1 |
| Patrick Bristow | Channing Elroy | Wig Master | 1 | 1 |
| Shaun Toub | Khalid Mohammed Bakr | Pinter Ranawat | 1 | 1 |
| Tony Winters | Admiral Gene Halverson | Peterman Employee | 1 | 1 |
| Wendy Worthington | Gila Shaw | Louise | 1 | 1 |
| Mik Scriba | Mr. Walters | Bomb Squad Guy, Cop #1 | 1 | 2 |
| Brian Leckner | Ben | Attendant | 1 | 1 |
| Daniel Hagen | Calvin Hopper | Rick | 1 | 1 |
| Ellen Ratner | Department of Army Security Guard May Stern | Ellen | 1 | 1 |
| Mo Gallini | Andre Jones | Tough Guy | 1 | 1 |
| Perry Anzilotti | Ted Rogers | Usher | 1 | 1 |
| Bart McCarthy | Retired Marine Master Sergeant George Hawkins | Cab Driver | 1 | 1 |
| Billy Williams | Francis "Cheech" Del Conte | Usher | 1 | 1 |
| Iqbal Theba | Ramesh Sengupta | Cabbie | 1 | 1 |
| John Cothran, Jr. | Alfred Holbrook | Man | 1 | 1 |
| Keith Sellon-Wright | Admiral Xavier Meade | Guy | 1 | 1 |
| Lyn Alicia Henderson | ER Nurse | Clerk | 1 | 1 |
| Marcelo Tubert | Nazar Boulos | Father | 1 | 1 |
| Pat Asanti | Ruben Williams | Electrician | 1 | 1 |
| Robert Mailhouse | Dr. Malcolm Lucas | Robert | 1 | 1 |
| Stephen Caffrey | Kevin Braddish | Arnie | 1 | 1 |
| Tom Gallop | Victor Sterling | Alan | 1 | 1 |
| Will Radford | Dale Gruber | Angry Guy | 1 | 1 |
| Armando Molina | Miguel Fernandez | Amigo | 1 | 1 |
| Ben Reed | Chief P.O. Ian Goetz | Male Nurse | 1 | 1 |
| Eamonn Roche | Hector Stuckey | Waiter | 1 | 1 |
| George Gerdes | Field Marshall Nigel Rand | Man #1 | 1 | 1 |
| Joel Polis | Ronald Ostrowski | Reilly | 1 | 1 |
| Leon Russom | Grandpa | Clayton | 1 | 1 |
| Rebecca Staab | Greta Boyen | Kristin | 1 | 1 |
| Scott Klace | Dr. Timothy Hass | Guard | 1 | 1 |
| Terry Rhoads | Stanley Borden | Father | 1 | 1 |
| Todd Jeffries | Thomas Gardiner | Blaine | 1 | 1 |
| Vito D'Ambrosio | Jonny Zucado | Cop | 1 | 1 |
| Alexandra Bokyun Chun | Phyllis Wu | Lotus | 1 | 1 |
| Chip Chinery | NCIS Employee Rodney Spence | Co-Worker #1 | 1 | 1 |
| Courtney Gains | Gary Silverstin | Clerk | 1 | 1 |
| Dan O'Connor | Pete Shaw | Young Cop | 1 | 1 |
| Mailon Rivera | Navy Commander Scott Bitterman | Cop #1 | 1 | 1 |
| Mark Holton | Sergeant Linn | David | 1 | 1 |
| Nigel Gibbs | Admiral Theodore Tully | Tenant #2 | 1 | 1 |
| Paul Perri | Man | Detective Danner | 1 | 1 |
| René Ashton | Justine Wolfe | Ex-Girlfriend | 1 | 1 |
| Todd Kimsey | Police Capt. Grant | Ned | 1 | 1 |
| Adrian Sparks | Hugo Radcliffe | Man | 1 | 1 |
| Bahni Turpin | Camille West | Waitress #1 | 1 | 1 |
| Toni Sawyer | Elizabeth Macy | Tenant #1 | 1 | 1 |
| Mark Fite | Walter Miller | Jack | 1 | 1 |
| Christopher Michael Moore | Miles Larson | Studio Guard | 1 | 1 |
Cast data from TVmaze, licensed CC BY-SA 4.0.