All 177 actors in both ER and The Unit
177 actors have appeared in both ER and The Unit, across 400 episodes. The most-credited is Laura Cerón, Nurse Chuny Marquez in ER and Ana Rocha in The Unit.
| Actor | In ER | In The Unit | Eps | Eps |
|---|---|---|---|---|
| Laura Cerón | Nurse Chuny Marquez | Ana Rocha | 219 | 1 |
| William H. Macy | Dr. David Morgenstern | President | 31 | 1 |
| Hank Stratton | Curt Oberg | Isaac Reed | 1 | 7 |
| Yara Martinez | Mia | Annie | 1 | 7 |
| Michael O'Neill | Col. Ken Kilner | Ron Cheals | 1 | 6 |
| April Parker Jones | Joyce | Principal Green | 1 | 2 |
| Conor O'Farrell | Richard Abbott | Major General Heath | 2 | 4 |
| Mike Genovese | Officer Al Grabarsky | Vince | 12 | 1 |
| Ned Bellamy | Detective | Lewis | 2 | 3 |
| Eric Ladin | Pvt. Thomas Perry | Blaylock | 1 | 1 |
| Jarreth Merz | Charles | Momed Salah | 3 | 1 |
| Jayne Taini | Marge Satterfield | Clerk | 1 | 1 |
| Shaun Duke | Detective, Painter | CIA Agent Dan Vorhees | 2 | 4 |
| Kirk B.R. Woller | Prisoner Transport Officer | Detective Penman | 1 | 2 |
| Sarah Avery | Coach Jenny | Samantha | 1 | 2 |
| Stana Katic | Blaire Collins | Special Agent Adrian Lane | 2 | 1 |
| Brent Jennings | Nat | Detective Litsinger | 3 | 1 |
| Bernard White | Addict seeking Rapid Detox | Khan | 1 | 1 |
| David Gianopoulos | John Dean / Bob Halderman | U.N. Chief Security Officer | 1 | 1 |
| David Purdham | Dr. Kallis | Mr. Green | 1 | 1 |
| Dylan Kenin | Louie | Randall Deacon | 1 | 2 |
| François Chau | Neuro Resident | Sub-Captain | 2 | 1 |
| Jeris Lee Poindexter | Nate, Rafe | Robot Operator | 2 | 1 |
| Max Arciniega | Nick Vasquez | Octavio Jr. | 1 | 1 |
| Vyto Ruginis | Paramedic Wright | Doyle | 3 | 2 |
| Natacha Roi | Serena Lipnicki | Capt. Lowry | 4 | 1 |
| Dwier Brown | Dr. David Herlihy | Ambassador Blashek | 3 | 1 |
| Dean Norris | Bomb Specialist Clark | Supervisor Marsh | 1 | 2 |
| Demetrius Grosse | Officer Newkirk | Guard #1 | 5 | 1 |
| Jack Guzman | Morgan | Water Guard | 2 | 1 |
| Tim Griffin | Captain John Evans | Morgan Eliot | 2 | 1 |
| Zoran Radanovich | Niko Kovač | Detainee #1, Mobster #1 | 3 | 2 |
| Clare Carey | Shauna | Helene Rouse | 1 | 1 |
| David Aaron Baker | Rufus Taylor | Bruce Smith | 1 | 1 |
| Jim Ortlieb | Cook | Principal | 1 | 1 |
| Michael J. Harney | Mr. Stehly | Crew Chief | 1 | 1 |
| Robin Weigert | Nicole | Annette Terry | 1 | 1 |
| Shannon Cochran | Mrs. Klingman | Capt. Lisa Tate | 1 | 1 |
| Shaun Toub | Butler | Misha Belikov | 1 | 1 |
| Shay Astar | Amy Thompson | Computer Hacker | 1 | 1 |
| Sonia Iris Lozada | Mrs. Lopez | Isabel | 1 | 1 |
| Ewan Chung | Chiu | Map Tech | 1 | 2 |
| George Gerdes | Jim Riley | Detective | 2 | 1 |
| Mary McCann | Mrs. Ramsey | Ruthie Cheals | 1 | 2 |
| Al Vicente | Luis | Manager | 1 | 1 |
| Carlos Lacamara | Ron Kennedy | Luis Inez Reale | 1 | 2 |
| Haley Ramm | Tasha | Amber | 1 | 1 |
| Henri Lubatti | Victor | Brian Mickey | 1 | 1 |
| James MacDonald | Officer Gary McWayne | Willis Meeks | 1 | 1 |
| Jose Pablo Cantillo | Juan Enriquez | Rock | 1 | 1 |
| Judith Moreland | Nurse Terry | Ruth Watson | 1 | 1 |
| Kim Estes | Lieutenant Higgins | Driver | 1 | 1 |
| Marco Rodríguez | Agent Serena | Cruz Mata | 1 | 1 |
| Mark Pellegrino | Nathan Conley | Gary Soto | 1 | 1 |
| Michael Shamus Wiles | Battalion Chief Bukata | General Navarro | 1 | 1 |
| Molly Schaffer | Bar Patron | Alice O'Neill | 1 | 1 |
| Sean McGowan | Food Court Guy | Sgt. Edison | 1 | 1 |
| Shirley Knight | Mrs. Burke | Mrs. Gaffney | 1 | 1 |
| Gregory Wagrowski | Walton, Herm Bullard | Petrov | 3 | 1 |
| Katie Mitchell | Shelley | Linda Kaplan, Sarah Branch | 2 | 2 |
| Andy Umberger | Dr. David Harvey | Agent Bluman | 2 | 1 |
| Casey Stengel | Tommy Gruger | Sgt. Vaughn (Tech) | 1 | 2 |
| Ntare Guma Mbaho Mwine | Assistant D.A., Paul Traylor | Isaias | 2 | 1 |
| Tia Texada | Gloria Lopez | Mariana Ribera | 1 | 2 |
| Alejandro Patiño | Best Man | Spanish Store Owner | 1 | 1 |
| Andrew Rothenberg | Pauly Johnson | Pool Player | 1 | 1 |
| Giovanni Lopes | Oscar Batista | Pablo | 1 | 1 |
| Isabella Hofmann | AIDS Clinic Doctor | Agent Terrell | 1 | 1 |
| Jamie McShane | Josh Rushing | Detective Renner | 1 | 1 |
| John Gleeson Connolly | Dan Udecker | Keller | 1 | 1 |
| Karina Logue | Radio Show Host | Dr. Passani | 1 | 1 |
| Kent Shocknek | Newsreporter | TV Newscaster | 1 | 1 |
| Lauri Johnson | Oncology Nurse | Neighbor | 1 | 1 |
| Lee Tergesen | Mr. Mullen | Alex Deckard | 1 | 1 |
| Marlene Forte | Mrs. Gonzalez | Maritza Calderon | 1 | 1 |
| Mel Winkler | Charles Sanberry | Avery Flowers | 1 | 1 |
| Nadège August | Mrs. Lemonier | Elsabet | 1 | 1 |
| Abdoulaye N'Gom | Dusty Father | Helper / Bakuto | 2 | 1 |
| Benjamin Brown | Cop, Lab Tech | Young George Blane | 2 | 1 |
| Julianna McCarthy | Mrs. Raskin | Margaret | 2 | 1 |
| Anoush NeVart | Sarshad | Scared Lady | 1 | 1 |
| Federico Dordei | Aldo | The Butcher | 1 | 1 |
| Jay Harik | Seiger | Orderly #1 | 1 | 1 |
| Mark Harelik | James | Secretary of State | 1 | 1 |
| Marshall Manesh | Babu | Bijan | 1 | 1 |
| Ned Schmidtke | Cal | Don Rohmer | 1 | 1 |
| Patti Yasutake | Kito | Judge Hatter | 1 | 1 |
| Rebecca Tilney | Judy Cochran | Lynette | 1 | 1 |
| Sandy Martin | Mrs. Zarian, Sister Helen | Woman with Cane | 2 | 1 |
| Toshi Toda | Japanese Businessman 1 | Premier Huang | 1 | 1 |
| Bruce Wright | George Dunleavy, Pilot Gordon | U.S. Ambassador | 2 | 1 |
| Veralyn Jones | Agent Vickery, Mrs. Powell | Mrs. Williams | 2 | 1 |
| David Hornsby | Strauss | Ricky | 1 | 1 |
| Deborah Van Valkenburgh | Louise Gavin | Madam | 1 | 1 |
| Jackie Debatin | Judy | Agent Suzanne Lee | 1 | 1 |
| Kevin Jackson | Harold Percy | Guard #2 | 1 | 1 |
| Maria McCann | Babette Fritzler | Susan Abernathy | 1 | 1 |
| Mario Quinonez, Jr. | Aaron Gonzalez | Refugee Boy | 1 | 1 |
| Patrick St. Esprit | Mr. Thorpe | Agent Inman | 1 | 1 |
| Richard Penn | Dave Donovan | Mr. Williams | 1 | 1 |
| Ali Dean | Cab Driver | Café Proprietor, Tribal Chief | 1 | 2 |
| Ameer Baraka | Reid | Sykes | 1 | 1 |
| Ariel Felix | Student #14 | Asst. General Arya | 1 | 1 |
| Colby French | Greg Becton | Welfare Man | 1 | 1 |
| Corey Stoll | Dr. Teddy Marsh | Bobby Carrol | 1 | 1 |
| Fiona Hale | Dorothy Holmes | Mrs. Frost | 1 | 1 |
| Larry Sullivan | Martin Pryor | Avner | 1 | 1 |
| Lisa Darr | Nadine Wilkes | Beverly | 1 | 1 |
| Ryun Yu | Baxter Yi | Raul | 1 | 1 |
| Scott Klace | Chris Halpern | Wilpon | 1 | 1 |
| Stephanie Fabian | Tesoro Delgado | Refugee | 1 | 1 |
| Terrell Lee | Russomante | Police Officer | 1 | 1 |
| Tom Kiesche | Officer Monroe | Gerald Thomas | 1 | 1 |
| Wendy Haines | Avila | Karen | 1 | 1 |
| Carlos Moreno Jr. | Mr. Ortiz | Gate Guard | 1 | 1 |
| David Gautreaux | Scruffy | Nina's Father | 1 | 1 |
| Duane R. Shepard, Sr. | Janitor | Fire Marshall | 1 | 1 |
| Emerson Brooks | Gonzalez | Loadmaster | 1 | 1 |
| Geno Monteiro | Fred | Secret Service Agent | 1 | 1 |
| Lillian Hurst | Mrs. Landeta | Senora Berenguer | 1 | 1 |
| Michelle Anne Johnson | Sarah Irving | Support Tech | 1 | 1 |
| Monique Gabriela Curnen | Nurse Blanca | Sgt. Rosas | 1 | 1 |
| Peter James Smith | Mr. Shimahara | Landon | 1 | 1 |
| Sam Murphy | John Murphy | Wounded Soldier | 1 | 1 |
| Yorgo Constantine | Trekkie | Armen Kochenko | 1 | 1 |
| Alain Uy | Burke | Employee, Operations Assistant | 1 | 2 |
| Adam Lieberman | Levine | FBI Agent | 1 | 1 |
| Anderson Goncalves | Matthew Jarre | Genari | 1 | 1 |
| Andy Fischer-Price | Tommy Cole | Daniel Miller | 1 | 1 |
| Caroline Choi | Angela Chang | University Student | 1 | 1 |
| Gabriel Salvador | Eddie | Monk #1 | 1 | 1 |
| Jack Wallace | Mr. Reynolds | Hank | 1 | 1 |
| James Geralden | Grieving Man | Douglas Myers | 1 | 1 |
| Jan Devereaux | Francis | Lee Rohmer | 1 | 1 |
| Lori Lively | Helen | Tom Ryan's Mother | 1 | 1 |
| Michael Cavanaugh | Suzanne's Dad | Committee Chair Locke | 1 | 1 |
| Sven Holmberg | Lars | Zjhokar | 1 | 1 |
| Tzi Ma | Mr. Yeung | Rudy Hartano | 1 | 1 |
| Wesley Leong | Newstand Guy | Shop Owner | 1 | 1 |
| Will Beinbrink | Wick | Henchman #1 | 1 | 1 |
| Victor Campos | Jeremy Barnes, Patient | Owner | 2 | 1 |
| Bryan Fabian | Fernando | Marcos | 1 | 1 |
| Jack Yang | Bevan Wong | Derek Chen | 1 | 1 |
| Sean Blakemore | Mario | African Soldier | 1 | 1 |
| Shannon Holt | Helen Palsey | Relief Worker | 1 | 1 |
| Don Oscar Smith | Bob | Happy Jack | 2 | 1 |
| Alex Nevil | Mr. Dorset | Flight Medic #1 | 1 | 1 |
| Amy Higgins | Victoria | Adria | 1 | 1 |
| Gary Carlos Cervantes | Cop | Security Guard | 1 | 1 |
| James Sutorius | Dr. Abrams | Arthur Chambers | 1 | 1 |
| Jarrod Bunch | Carranza | Bouncer #1 | 1 | 1 |
| Kamel Haddad | Watnick | Father | 1 | 1 |
| Nancy Youngblut | Sarah Howe | Ila Neihaus | 1 | 1 |
| Robert Covarrubias | Manny Lopez | Officer | 1 | 1 |
| Winston J. Rocha | Officer Eddie Escobar | Store Owner | 1 | 1 |
| Bob Larkin | Junior Neurologist | Mr. Dwayne Oscarsson | 1 | 1 |
| Javier Roceros | Maintenance Guy | Fisherman | 1 | 1 |
| Joanne Rubino | Mom | Sam's Aunt | 1 | 1 |
| Paul Renteria | Custodian | Deliveryman | 1 | 1 |
| Elizabeth Sampson | Norma Beckwith | Adult Woman | 1 | 1 |
| Kente Scott | Taylor Sparks | Dead Soldier | 1 | 1 |
| Luis Moncada | Rogelio | Elias Lianez | 1 | 1 |
| Matt Doherty | Eli Emerson | Henderson | 1 | 1 |
| Annie O'Donnell | Eve | Little Old Lady | 1 | 1 |
| Dee Anne Helsel | Deanne | Edna | 1 | 1 |
| Eltony Williams | Rossen | Officer Hitchner | 1 | 1 |
| Evgeniy Lazarev | Ivo Guter | Russian Ambassador | 1 | 1 |
| Bryce Blue | Silas | Kieran | 1 | 1 |
| Ilia Volok | Kovalev | Deputy Grubo | 1 | 1 |
| Jarrod Crawford | David "Diamond Z" Zachary | Mutt | 1 | 1 |
| Jeffrey Hutchinson | Richard Weingarten | Building Handyman | 1 | 1 |
| Roz Witt | Saleswoman | Teller | 1 | 1 |
| James Kiriyama-Lem | Dr. Mitsuma | Crew Member | 1 | 1 |
| Tim Halligan | Howard | Larry Crumpler | 1 | 1 |
| Cari Zoch | Brenda | Waitress | 1 | 1 |
| Kevin Fry | Detective Demetras | Tom Ryan's Stepfather | 1 | 1 |
| Nigel Gibbs | Matson | General Hayes | 1 | 1 |
Cast data from TVmaze, licensed CC BY-SA 4.0.