All 89 actors in both NCIS and Quantum Leap
89 actors have appeared in both NCIS and Quantum Leap, across 603 episodes. The most-credited is Melinda McGraw, Diane Sterling in NCIS and Laura Downey in Quantum Leap.
| Actor | In NCIS | In Quantum Leap | Eps | Eps |
|---|---|---|---|---|
| Melinda McGraw | Diane Sterling | Laura Downey | 6 | 1 |
| Scott Bakula | Special Agent Dwayne Cassius "King" Pride | John Beckett | 4 | 2 |
| John D'Aquino | Ken Ashmore | Frank LaMotta | 1 | 3 |
| John Finn | Marine Commandant Charles T. Ellison | Admiral Spencer | 3 | 1 |
| Michael Bellisario | Charles Sterling | Billy, Kid #2, Little Boy | 4 | 4 |
| Susan Diol | Doris Sawyer, Dr. Leslie Burke | Beth Calavicci | 2 | 2 |
| Troian Bellisario | Sara McGee | Teresa Bruckner | 3 | 1 |
| Bruce McGill | Henry Rogers | Al The Bartender, Weird Ernie | 1 | 2 |
| CCH Pounder | Jefferson Parish Coroner Doctor Loretta Wade | Mama Harper | 2 | 1 |
| Fran Bennett | Mary Elaine Smith | Marie Billings, Ada Simpson | 2 | 4 |
| James Morrison | CIA Assistant Director Jonathan Overmeier, U.S. Senator John Phillips | Joe Deever | 2 | 1 |
| K Callan | Bertha Jones-Delacroix, Grace Mullen | Lenore Mackenzie | 2 | 1 |
| Kelli Williams | NCIS Special Agent Maureen Cabot | Shannon | 2 | 1 |
| Peter Jason | Marine Sergeant Major Robert King | Kilpatrick | 2 | 1 |
| Robert Pine | Congressman Theodore Randolph, Golfer Ben | Ted | 2 | 1 |
| Angelo Tiffe | Jed Hamilton | Carl Morgan | 1 | 1 |
| Claudia Christian | Belgian Vsse Officer Louise Moreau | Allison Grimsley | 1 | 1 |
| Danny Nucci | Gordon Fremont | Tony Pronti | 1 | 1 |
| David Tom | Maple | Daniel Burke | 1 | 1 |
| Eric Bruskotter | Lester | Beau, Glen, Red | 1 | 3 |
| Gregory Itzin | FBI Director, Spencer Downing | Sam Phillips | 3 | 1 |
| Jennifer Rhodes | Claudia | Agnes Stevens | 1 | 1 |
| John Kapelos | Vice Principal Vic Castor | Dr. Mustafa El Razul | 1 | 1 |
| Kim Robillard | Dwayne Parker | Stern | 1 | 1 |
| Marcus Giamatti | Victor Tillman | Rick Upfield | 1 | 1 |
| Michael Beach | Metro Detective Robert Flowers | Nathaniel Simpson | 1 | 1 |
| Morgan Weisser | Vincent Hanlan | Tim Stoddard | 1 | 1 |
| Raphael Sbarge | Rupert Kritzer | Will | 1 | 1 |
| Richard Riehle | Walt Osorio | Clifford Vargas, Lieutenant Lannon | 2 | 2 |
| David Pressman | Dave Siebel, Lewis Dacey | Frat Boy | 2 | 1 |
| Olivia Burnette | Sarah Lowel | Katie Beckett, Susan Bruckner | 1 | 2 |
| Scott Lawrence | DEA Agent Raymond Frank, Navy Captain Thomas Lind | Tibby Johnson | 2 | 1 |
| Stephen Lee | Chuck Bayliss | Bo Loman | 1 | 3 |
| Beverly Leech | Vice Admiral Janet Kleibor | Catherine Farrington | 1 | 1 |
| Casey Sander | Ed Gantry | Warren Monroe | 1 | 1 |
| Christopher Allport | Metro Police Cpt. Dan Karzin | Alan Ripley | 1 | 1 |
| Daniel Roebuck | Port Security Chief Matthew Lake | Neil Lindhurst | 1 | 1 |
| Deborah Strang | Diane Warner | Aggie | 1 | 1 |
| George Wyner | Randall Worthington | Ben Harris | 1 | 1 |
| Glenn Morshower | Cmdr. Robert Peters | Grady | 1 | 1 |
| Jason Beghe | Blake Martin | Det. Sgt. Roger Skaggs | 1 | 1 |
| John Allen Nelson | JSOC Vice Admiral Lloyd Manditsky | Capt. Bill 'Bird Dog' Birdell | 1 | 1 |
| Kate McNeil | Commander Green | Olivia Barrett Covington | 1 | 1 |
| Louis Mustillo | Emilio "Freckles" Zucado | Mario | 1 | 1 |
| Michael McGrady | Walter Dunn | Oscar | 1 | 1 |
| Patricia Richardson | Judy Price Fielding | Rachel Porter | 1 | 1 |
| Peter Onorati | Chief of the Boat | Rick | 1 | 1 |
| Robert Costanzo | Jimmy Napalitano | Chuck Thompson | 1 | 1 |
| Sean O'Bryan | David Shields | Phillip Ashcroft | 1 | 1 |
| Stacy Edwards | Commander Janice Byers | Elizabeth Spokane | 1 | 1 |
| Tim De Zarn | David Runion | Stan | 1 | 1 |
| Tom Everett | CIA Head of Intelligence Kirkwood Zaysen | Deputy Sheriff Hazlitt | 1 | 1 |
| Josh Coxx | FLETC Instructor Hal Sterling, Navy Captain Paul Smith | Officer Milardi | 2 | 1 |
| Anthony Palermo | Nicholas “Nick” Bodeen A.K.A. Navy Commander | Ronnie Chambers | 1 | 1 |
| Basil Wallace | Delphin Abaka | Jasper "Jazz" Boone | 1 | 1 |
| Daniel Zacapa | Detective Martin Alonzo | Officer Montero | 1 | 1 |
| Diane Delano | Dee Dee Chesney | Prostitute | 1 | 1 |
| Erich Anderson | Jack Canton | Steve Slater | 1 | 1 |
| H. Richard Greene | Thomas Victor | Dr. Hardy | 1 | 1 |
| Judy Kain | Gladys Stone | Waitress | 1 | 1 |
| Katherine Cortez | Thelma McKeever | Sophie | 1 | 1 |
| Kenneth Tigar | Diggar Aldridge | Ben Steiner | 1 | 1 |
| Lee Garlington | Mary Hanlan | Nurse Chatam | 1 | 1 |
| Max Gail | Sam Loomis | George Sanders | 1 | 1 |
| Mimi Kuzyk | Ginger Stevenson | Dr. Donna Eleese | 1 | 1 |
| Peter Murnik | Admiral Michael Caplinger | Welles | 1 | 1 |
| Dan Ziskie | Captain Vetter | Sergeant Riley | 1 | 1 |
| Edward Edwards | Congressman | Professor Davenport | 1 | 1 |
| Geoffrey Lower | Navy Cmdr. Robert Morris | Lt. Richard Montgomery | 1 | 1 |
| Gregg Binkley | Bob Stivers | Deputy | 1 | 1 |
| Larry Poindexter | Dr. Berman | Capt. Tony LaMott | 1 | 1 |
| Matthew Ashford | Rick Martel | TV Husband | 1 | 1 |
| Brian George | Dr. Ameen Temani | Ben | 1 | 1 |
| Brian Leckner | Ben | Frat Boy | 1 | 1 |
| Larry Brandenburg | Hubble | Commander Hugh Dobbs | 1 | 1 |
| Penny Peyser | Judge Susan Delphy | ADA Nancy Hudson | 1 | 1 |
| Aaron Lustig | Doctor Victor Kalsa | Judge Bowers | 1 | 1 |
| Cyd Strittmatter | Joanne Wright | Hippie Girl | 1 | 1 |
| Edmund L. Shaff | Security Guard George | Minister | 1 | 1 |
| Mary Pat Gleason | Nurse Wells | Mrs. Thompson | 1 | 1 |
| William Morgan Sheppard | Marcin Jerek | Gooshie, the Miner | 1 | 1 |
| Javi Mulero | Earl Grieve | Taco Man | 1 | 1 |
| Michael Holden | Dr. Wayne Dobson | Herb Stein | 1 | 1 |
| Mik Scriba | Mr. Walters | Coach Donnelly | 1 | 1 |
| Nigel Gibbs | Admiral Theodore Tully | Waiter | 1 | 1 |
| Byrne Offutt | Judd Kearns | Leon | 1 | 1 |
| Scott Menville | Army Sergeant Donald "Donny" Pretorius | Cameron Wilson | 1 | 1 |
| Barbara Tarbuck | Grandma | Esther | 1 | 1 |
| Hap Lawrence | Lenny | Bartender | 1 | 1 |
Cast data from TVmaze, licensed CC BY-SA 4.0.