# Cast of ER

ER is an American medical drama television series created by Michael Crichton that aired on NBC from September 19, 1994, to April 2, 2009. It was produced by Constant c Productions and Amblin Television, in association with Warner Bros. Television. The series follows the inner life of the emergency room (ER) of fictional Cook County General Hospital in Chicago, and various critical issues faced by the room's physicians and staff.
ER featured a large ensemble cast that changed dramatically over its long run. The main cast was augmented by a wealth of recurring characters and award-winning guest stars.

## Main cast

The original starring cast consisted of Anthony Edwards as Dr. Mark Greene, George Clooney as Dr. Douglas "Doug" Ross, Sherry Stringfield as Dr. Susan Lewis, Noah Wyle as medical student (later Dr.) John Carter, and Eriq La Salle as Dr. Peter Benton. Julianna Margulies guest starred in the pilot as Nurse Carol Hathaway before becoming part of the regular cast.
The first additions to the main cast came in Season 2 with Gloria Reuben signing on as Physician Assistant Jeanie Boulet (recurring character in Season 1), and in Season 3 with Laura Innes as Dr. Kerry Weaver (recurring character in Season 2). In Season 4, Maria Bello signed on as Dr. Anna Del Amico (recurring character at the end of Season 3) and Alex Kingston joined the cast as Dr. Elizabeth Corday. Season 5 saw the addition of Kellie Martin as medical student Lucy Knight.
George Clooney's departure towards the end of Season 5 started a major cycle of main cast changes over the next few years. Season 6 opened with the addition of Paul McCrane as Dr. Robert "Rocket" Romano (recurring character in both Seasons 4 and 5), Croatian actor Goran Višnjić as Dr. Luka Kovač, and Michael Michele as Dr. Cleo Finch. A bit later in the season Erik Palladino joined as Dr. Dave Malucci, and Ming-Na returned to the series as Dr. Jing-Mei "Deb" Chen, reprising a recurring character she portrayed in Season 1. Soon after, Maura Tierney was added as Nurse (later Dr.) Abigail "Abby" Lockhart. Season 8 saw the arrival of Sharif Atkins as medical student (later Dr.) Michael Gallant, as well as the return of Dr. Susan Lewis when Sherry Stringfield reprised her role after having left the series in Season 3.
Mekhi Phifer joined the cast in Season 9 as Dr. Gregory "Greg" Pratt (recurring character at the end of Season 8). Season 10 saw the addition of Parminder Nagra as medical student (later Dr.) Neela Rasgotra and Linda Cardellini as Nurse Samantha "Sam" Taggart. Shane West joined the cast in Season 11 as Dr. Ray Barnett and Scott Grimes became part of the main cast in Season 12 as Dr. Archie Morris (recurring character in Seasons 10 and 11). Season 13 saw the addition of John Stamos as Dr. Anthony "Tony" Gates, reprising a role he had originated in Season 12 when he portrayed Gates the paramedic/medical student. Season 15 saw the final additions to the main cast, with David Lyons signing on as Dr. Simon Brenner (recurring character towards the end of Season 14) and Angela Bassett as Dr. Catherine "Cate" Banfield.
Notably, of the 26 main cast members that starred throughout ER's 15-season run, only seven were not featured in the final season: Gloria Reuben, Maria Bello, Kellie Martin, Michael Michele, Erik Palladino, Ming-Na, and Sharif Atkins. In addition, only four main cast members never made a return appearance of any type following their original stint: Maria Bello, Kellie Martin, Erik Palladino, and Mekhi Phifer.

### Main characters

| Actor | Character | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons | Seasons |
| Actor | Character | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| Anthony Edwards | Mark Greene | M | M | M | M | M | M | M | M | | | | | | | S |
| George Clooney | Doug Ross | M | M | M | M | M | S.G | | | | | | | | | S |
| Sherry Stringfield | Susan Lewis | M | M | M | | | | | M | M | M | M | M | | | S |
| Noah Wyle | John Carter | M | M | M | M | M | M | M | M | M | M | M | R | | | S |
| Julianna Margulies | Carol Hathaway | M | M | M | M | M | M | | | | | | | | | S |
| Eriq La Salle | Peter Benton | M | M | M | M | M | M | M | M | | | | | | | S |
| Gloria Reuben | Jeanie Boulet | R | M | M | M | M | M | | | | | | | | S.G | |
| Laura Innes | Kerry Weaver | | R | M | M | M | M | M | M | M | M | M | M | M | | S |
| Maria Bello | Anna Del Amico | | | R | M | | | | | | | | | | | |
| Alex Kingston | Elizabeth Corday | | | | M | M | M | M | M | M | M | M | | | | S |
| Kellie Martin | Lucy Knight | | | | | M | M | | | | | | | | | |
| Paul McCrane | Robert Romano | | | | R | R | M | M | M | M | M | | | | | S.G |
| Goran Višnjić | Luka Kovač | | | | | | M | M | M | M | M | M | M | M | S | S |
| Michael Michele | Cleo Finch | | | | | | M | M | M | | | | | | | |
| Erik Palladino | Dave Malucci | | | | | | M | M | M | | | | | | | |
| Ming-Na | Jing-Mei Chen | R | | | | | M | M | M | M | M | M | | | | |
| Maura Tierney | Abby Lockhart | | | | | | M | M | M | M | M | M | M | M | M | M |
| Sharif Atkins | Michael Gallant | | | | | | | | M | M | M | S.G | R | | | |
| Mekhi Phifer | Greg Pratt | | | | | | | | R | M | M | M | M | M | M | M |
| Parminder Nagra | Neela Rasgotra | | | | | | | | | | M | M | M | M | M | M |
| Linda Cardellini | Sam Taggart | | | | | | | | | | M | M | M | M | M | M |
| Shane West | Ray Barnett | | | | | | | | | | | M | M | M | | R |
| Scott Grimes | Archie Morris | | | | | | | | | | R | R | M | M | M | M |
| John Stamos | Tony Gates | | | | | | | | | | | | G | M | M | M |
| David Lyons | Simon Brenner | | | | | | | | | | | | | | R | M |
| Angela Bassett | Cate Banfield | | | | | | | | | | | | | | | M |
* 1 2 3 4 5 6 7 8 9 The actor was credited along with the main cast members in the episodes they appeared in.

### Departures from the main cast

Sherry Stringfield's first departure from the show was in 1996, when her character, Susan Lewis, moved to Phoenix, Arizona, in the Season 3 episode "Union Station." In 2001, Stringfield returned to the series, reprising her role of Dr. Lewis, in the Season 8 episode "Never Say Never." She departed again after the Season 12 premiere, "Cañon City." This departure was not depicted, but was mentioned by character Kerry Weaver two episodes later, in "Man With No Name", as not coming in due to interviewing for a tenured position, having been denied tenure at County, and again later in "Wake Up," when Weaver explains that Susan accepted a tenure-track position at a hospital in Iowa City, Iowa. Stringfield returned once again for the series finale.
After playing Anna Del Amico for one season, Maria Bello was not part of the ensemble cast when Season 5 began. Like Susan Lewis's second exit, her character's departure was mentioned but not depicted: in the season premiere, "Day for Knight," John Carter explains to new medical student Lucy Knight that the locker she is inheriting previously belonged to Del Amico, who returned to Philadelphia to rejoin a prestigious Pediatrics unit there and be with her family and boyfriend.
George Clooney left the show in the Season 5 episode "The Storm (Part II)," when his character, Doug Ross, resigned before being fired for his involvement in a patient's death. Clooney made a cameo appearance in the Season 6 episode "Such Sweet Sorrow" when his character reunited with Carol Hathaway and appeared in the Season 15 episode "Old Times" where his character was the attending physician caring for a terminal organ donor in Seattle.
Gloria Reuben departed early in Season 6, in the episode "The Peace of Wild Things," when her character, Jeanie Boulet, decided to become a stay-at-home mom and care for her newly adopted HIV-positive baby. Reuben returned in the Season 14 episode "Status Quo" when her character's son was brought into the ER.
Kellie Martin, who played medical student Lucy Knight, left the series midway through Season 6 in the episode "All in The Family," when her character was killed by a patient with undiagnosed schizophrenia; his psychotic break occurred before a backed-up psychiatry department could arrive in the ER for a consult.
Julianna Margulies left the show at the end of Season 6, in the episode "Such Sweet Sorrow," when her character, Carol Hathaway, decided on the spur of the moment to go to Seattle, Washington, and reunite with Doug Ross, her true love and the father of her twin daughters. Margulies returned in the Season 15 episode "Old Times," with her character coordinating transplant efforts from a single organ donor in Seattle.
Erik Palladino departed early in Season 8, in the episode "Never Say Never," after his character, Dave Malucci, was fired by an angry Kerry Weaver. While she putatively fired him for having sex with an off-duty female EMT, he was officially fired for a mis-diagnosis that led to a patient's death, which in tandem with his error-ridden record at County meant that the hospital would not give him any more chances.
Eriq La Salle's character, Peter Benton, departed in the Season 8 episode "I'll Be Home for Christmas." He took a job with a set schedule at another hospital in order to spend more time with his son, Reese, and his girlfriend, former fellow ER doctor Cleo Finch. La Salle returned for two more episodes in Season 8 and then again for two episodes in Season 15, including the series finale.
Michael Michele's character, Cleo Finch, departed in the Season 8 episode "I'll Be Home for Christmas" with her boyfriend, and fellow doctor, Peter Benton, after having previously taken a job at the same hospital (in fact it was she who arranged the interview which resulted in Benton's job offer). Michele made a cameo appearance in the Season 8 episode "On the Beach" at Mark Greene's funeral. Cleo did not return to the show after that, but Peter confirmed they had gotten married and were raising Reese together in the series finale.
Anthony Edwards's character, Mark Greene, died of a brain tumor in Season 8's penultimate episode, "On the Beach." Anthony Edwards was still credited in the Season 8 finale episode "Lockdown" as a tribute to what both the actor and character had meant to the series. Edwards returned in the Season 15 episode "Heal Thyself" where he appeared in multiple flashback scenes to give insight into the past of Angela Bassett's character.
Paul McCrane's character, Robert Romano, whose arm had been severed just above the elbow by a helicopter's tail rotor in the Season 9 premiere "Chaos Theory," died in the Season 10 episode "Freefall." A helicopter that was taking off from the hospital roof was buffeted by strong winds, causing it to crash on the roof and plummet over the side of the building; it fell into a crowded ambulance bay and landed squarely on Romano. McCrane returned in the Season 15 episode "Heal Thyself" in a cameo set in 2002 (the current day of that episode was 2008).
Sharif Atkins left the series in the Season 10 episode "Where There's Smoke," when his character, Michael Gallant, revealed that the Army was sending him to Iraq. Atkins returned for two episodes during Season 11 where he is seen serving duty in Iraq and then for four episodes during Season 12 when he marries Neela Rasgotra before redeploying to Iraq where he is killed by an improvised explosive device while serving a second tour.
Alex Kingston's character, Elizabeth Corday, departed early in Season 11 in the episode "Fear" after getting in trouble for performing an illegal organ donation procedure; rather than being summarily fired, County offered her a demotion to a non-tenured position, but she turned it down and opted to return to England instead. Kingston returned for two episodes in Season 15, including the series finale.
Ming-Na departed midway through Season 11 in the episode "Twas The Night" when her character, Jing-Mei Chen, resigned in order to take care of her ailing father, whom she later euthanized. This was the second time her character left County General: in Season 1, medical student "Deb" Chen appeared in an eight episode story arc which concluded with her leaving medical school after accidentally leaving a guide wire in a patient's chest, deciding she was better suited to research than to applied medicine.
Noah Wyle left in the Season 11 finale, "The Show Must Go On." His character, John Carter, having received tenure at County, decided to reunite with his girlfriend Kem Likasu (portrayed by Thandiwe Newton). Wyle returned for four episodes during Season 12 where he is seen practicing medicine in Darfur and then for five episodes during Season 15 when he needed a life-saving kidney transplant.
Laura Innes left midway through Season 13 in the episode "A House Divided," when a reluctant Luka Kovač was forced by budget cuts to fire her character, Kerry Weaver due to her high salary. After bracing for a battle to keep her position, and in spite of the fact that Kovač realized he must find a way to keep her on staff, Weaver ultimately decided to resign from County and accept a job offer from a television station in Miami, Florida. Innes returned for two episodes in Season 15, including the series finale.
Shane West left in the Season 13 finale, "The Honeymoon Is Over," after his character, Ray Barnett got hit by a truck, lost both his legs and returned to Baton Rouge with his mother to recuperate. West returned for three episodes during Season 15 when his character reunited with Neela Rasgotra.
Goran Višnjić, who played the character of Luka Kovač, departed in the Season 13 finale, "The Honeymoon Is Over," when he left for Croatia to care for his ailing father. He returned for seven episodes in Season 14 to wrap up his medical storyline and then made a brief appearance in the Season 15 episode "The Book of Abby" where he, Abby, and their son Joe embark on their new life together.
Mekhi Phifer departed in the Season 15 premiere, "Life After Death," when his character, Greg Pratt, died in the ER as the result of blast injuries suffered in an ambulance explosion.
Maura Tierney, who played the character of Abby Lockhart, departed early in Season 15 in the episode "The Book of Abby" with her husband Luka Kovač. Along with their son Joe, they presumably headed to Boston, where Abby had accepted a new job. She attempted to leave the ER quietly, however the rest of the staff made it known how much they would miss her. Nurse Haleh Adams showed Abby a hidden wall with the locker labels of all the past staff members since season one, with the exceptions of Carter (who refused to deface government property) and Boulet (who took hers as a memento when she departed in Season 6). Other names on the wall include departed former characters as well as some prominent writers and producers. Abby then left the ER and met Luka and her son Joe outside to embark on their new life together. Tierney returned in the Season 15 episode "Shifting Equilibrium" in a cameo during a phone conversation with Neela Rasgotra.

## Supporting cast
### Desk clerks and other non-medical hospital staff

| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Abraham Benrubi | Jerry Markovic | Desk Clerk | 1994–1999, 2002–2006, 2008–2009 |
| Glenn Plummer | Timmy Rawlins | Desk Clerk | 1994–1995, 2006–2007 |
| Christine Healy | Harriet Spooner | Hospital Administrator | 1994–1999 |
| Małgorzata Gebel | (Dr.) Bogdanilivestsky "Bob" Romansky | ER Aide | 1994–1995 |
| Lisa Zane | Diane Leeds | Risk Management Administrator | 1995 |
| Rolando Molina | Rolando | Desk Clerk | 1995–1996 |
| Kristin Minter | Miranda "Randi" Fronczak | Desk Clerk | 1995–2003 |
| Charles Noland | E. Ray "E-Ray" Bozman | Desk Clerk | 1995–1997 |
| Skip Stellrecht | Miller | Hospital Chaplain | 1996 |
| Brent Jennings | Nat | Custodian | 1997–2000 |
| Mariska Hargitay | Cynthia Hooper | Desk Clerk | 1997–1998 |
| Jeff Cahill | Tony Fig | Transport Dispatcher | 1998–1999 |
| Djimon Hounsou | Mobalage Ekabo | Custodian | 1999 |
| Akosua Busia | Kobe "Kubby" Ekabo | Hospital Cafeteria Worker | 1999 |
| Andrew Bowen | Andrew "Andy" | Desk Clerk Temp | 1999–2000 |
| Pamela Mala Sinha | Amira | Desk Clerk | 1999–2001, 2003–2005 |
| Troy Evans | Frank Martin | Desk Clerk | 1994, 2000–2009 |
| Julie Delpy | Nicole | ER Aide | 2001 |
| Jordan Calloway | K.J. Thibeaux | Volunteer | 2005–2006 |
| Charlayne Woodard | Angela Gilliam | Medical Staff Affairs Manager | 2006–2007 |
| Jesse Borrego | Javier | Desk Clerk | 2007–2008 |
| Reiko Aylesworth | Julia Dupree | Hospital Chaplain | 2007–2008 |

### Nurses and other medical staff

| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Conni Marie Brazelton | Conni Oligario | ER Nurse | 1994–2003 |
| Suzanne Carney | Janet | OR Nurse | 1994–2000 |
| Ellen Crawford | Lydia Wright | ER Nurse | 1994–2003, 2009 |
| Deezer D | Malik McGrath | ER Nurse | 1994–2009 |
| Yvette Freeman | Haleh Adams | ER Nurse | 1994–2009 |
| Vanessa Marquez | Wendy Goldman | ER Nurse | 1994–1997 |
| Lily Mariye | Lily Jarvik | ER Nurse | 1994–2009 |
| Dinah Lenney | Shirley | Surgical Charge Nurse | 1995–2004, 2006–2009 |
| Laura Cerón | Ethel "Chuny" Márquez | ER Nurse | 1995–2009 |
| Lucy Rodriguez | Bjerke | Nurse | 1996, 2000–2003 |
| Bellina Logan | Kit | ICU, Pediatrics, and Surgical Nurse | 1996–2003, 2005, 2008 |
| Jenny O'Hara | Rhonda Sterling | Temp Nurse | 1996 |
| Meg Thalken | Dee McManus | Flight Nurse | 1996, 1999–2001, 2005, 2008 |
| Deborah May | Mary Cain | Nursing Director | 1996–1997, 2002 |
| Gedde Watanabe | Yosh Takata | ER Nurse | 1997–2003 |
| Kyle Richards | Dori Kerns | ER Nurse | 1998–2006 |
| Penny Johnson Jerald | Lynette Evans | Nurse Practitioner | 1998–1999 |
| Elizabeth Rodriguez | Sandra | OB Nurse | 1999–2001 |
| Morris Chestnut | Frank "Rambo" Bacon | ICU Nurse | 2000 |
| Mary Heiss | Mary | ER Nurse | 2000–2008 |
| Nadia Shazana | Jacy | Nurse | 2001–2008 |
| Linda Shing | Corazon | ICU Nurse | 2001–2003 |
| Sumalee Montano | Duvata Mahal | ER Nurse | 2002–2005 |
| Donal Logue | Chuck Martin | Flight Nurse | 2003–2005 |
| Cynthia Cervini | Anna Waldron | Nurse | 2004, 2005 |
| Kristen Johnston | Eve Peyton | Nurse Manager | 2005 |
| April Lee Hernández | Inez | ER Nurse | 2005–2006 |
| Angel Laketa Moore | Dawn Archer | ER Nurse | 2006–2009 |
| Kip Pardue | Ben Parker | ER Nurse | 2006–2007 |
| Nasim Pedrad | Suri | ER Nurse | 2007–2009 |

### Secondary doctors and medical students

| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Scott Jaeck | Dr. Steve Flint | Chief of Radiology | 1994–1996, 1999–2000, 2002 |
| William H. Macy | Dr. David Morgenstern | Chief of Surgery, Chief of Emergency Medicine | 1994–1998, 2009 |
| Tobin Bell | Dr. Wertz | Hospital Administrator | 1994 |
| John Terry | Dr. David "Div" Cvetic | Psychiatrist | 1994 |
| Tyra Ferrell | Dr. Sarah Langworthy | Surgical Resident | 1994 |
| Sam Anderson | Dr. Jack Kayson | Chief of Cardiology | 1994–1999, 2001–2005, 2007 |
| Rick Rossovich | Dr. John "Tag" Taglieri | Orthopedic Surgeon | 1994–1995 |
| Pierre Epstein | Dr. Alex Bradley | Chief of Staff | 1994–1996 |
| CCH Pounder | Dr. Angela Hicks | Surgical Attending | 1994–1997 |
| Amy Aquino | Dr. Janet Coburn | Chief of Obstetrics and Gynecology | 1994–2009 |
| Michael Ironside | Dr. William "Wild Willy" Swift | Chief of Emergency Medicine | 1995, 1998, 2002 |
| Christine Elise | Harper Tracy | Medical Student | 1995–1996 |
| David Spielberg | Dr. Neil Bernstein | Chief of Pediatrics | 1995 |
| Michael B. Silver | Dr. Paul Myers | Psychiatrist | 1995, 1997–2000, 2003, 2005, 2008 |
| Perry Anzilotti | Dr. Perry | Anesthesiologist | 1995–2004, 2006, 2008 |
| Ron Rifkin | Dr. Carl Vucelich | Cardiothoracic Surgeon | 1995–1996 |
| Megan Cole | Dr. Alice Upton | Pathologist | 1996, 1998, 2000–2001, 2003 |
| Matthew Glave | Dr. Dale Edson | Surgical Intern/Resident | 1996–1999, 2001–2002 |
| Omar Epps | Dr. Dennis Gant | Surgical Intern | 1996–1997 |
| John Aylward | Dr. Donald Anspaugh | Chief of Staff, General Surgeon | 1996–2008 |
| Jorja Fox | Dr. Maggie Doyle | ER Intern/Resident | 1996–1999 |
| Glenne Headly | Dr. Abby Keaton | Pediatric Surgeon | 1996–1997 |
| Don Perry | Dr. Sam Breedlove | Surgeon | 1996–1997 |
| Jami Gertz | Dr. Nina Pomerantz | Psychiatrist | 1997 |
| Harry Lennix | Dr. Greg Fischer | Infectious Disease Specialist | 1997 |
| Iqbal Theba | Dr. Zagerby | Ophthalmologist | 1997, 2001 |
| Ted Rooney | Dr. Tabash | Neonatologist | 1997–1998 |
| Chad Lowe | George Henry | Medical Student | 1997, 2005 |
| Joel de la Fuente | Ivan Fu | Medical Student | 1997 |
| Justin Henry | James Sasser | Medical Student | 1997 |
| Clancy Brown | Dr. Ellis West | Associate ER Attending Physician | 1997–1998 |
| Dennis Boutsikaris | Dr. David Kotlowitz | Surgeon | 1998 |
| James Le Gros | Dr. Max Rocher | Pediatrician | 1998 |
| David Brisbin | Dr. Alexander Babcock | Anesthesiologist | 1998–2002 |
| Vince Vieluf | Bernard Gamely | Medical Student | 1998 |
| Mare Winningham | Dr. Amanda Lee | Chief of Emergency Medicine | 1998–1999 |
| Carl Lumbly | Dr. Graham Baker | Plastic Surgeon | 1999 |
| Tom Gallop | Dr. Roger Julian | Chief of Genetics | 1999 |
| John Doman | Dr. Carl DeRaad | Chief of Psychiatry | 1999–2001, 2003 |
| Alan Alda | Dr. Gabriel "Gabe" Lawrence | ER Attending Physician | 1999 |
| Elizabeth Mitchell | Dr. Kim Legaspi | Psychiatrist | 2000–2001 |
| Lourdes Benedicto | Dr. Rena Trujillo | Pediatrics Intern | 2001 |
| Eddie Shin | Stanley Mao | Medical Student | 2001 |
| Christopher Grove | Dr. Marty Kline | Orthopedic Surgeon | 2002–2003, 2006 |
| Leslie Bibb | Erin Harkins | Medical Student | 2002–2003 |
| Don Cheadle | Paul Nathan | Medical Student | 2002 |
| Bruno Campos | Dr. Eddie Dorset | Vascular Surgeon | 2003 |
| Glenn Howerton | Dr. Nick "Coop" Cooper | ER Resident | 2003 |
| Nicholas D'Agosto | Andy | Medical Student | 2003 |
| Shi Ne Nielson | Sheila | Medical Student | 2003–2004 |
| Rossif Sutherland | Lester Kertzenstein | Medical Student | 2003–2004 |
| L. Scott Caldwell | Dr. Megan Rabb | Director of Neonatology | 2004, 2006 |
| Jeremy Glazer | David | Medical Student | 2004 |
| Paul Blackthorne | Dr. Jeremy Lawson | Interventional Radiologist | 2004 |
| Maury Sterling | Dr. Nelson | Psychiatrist | 2004, 2006 |
| Andy Powers | Dr. Howard Ritzke | ER Intern | 2004 |
| Jillian Bach | Penny Nicholson | Medical Student | 2004–2006 |
| Leland Orser | Dr. Lucien Dubenko | Surgical Attending, Chief of Surgery | 2004–2009 |
| Giovannie Pico | Ludlow | Medical Student | 2004–2005 |
| Sara Gilbert | Dr. Jane Figler | ER Intern/Resident | 2004–2008 |
| Eion Bailey | Jake Scanlon | Medical Student | 2004–2005 |
| Anthony Giangrande | Dr. Jeremy Munson | ER Intern | 2005 |
| Michael Spellman | Dr. Jim Babinski | ER Intern | 2005 |
| Damali Scott | Dr. Lana Clemons | ER Intern | 2005 |
| Corey Stoll | Dr. Teddy Marsh | ER Intern | 2005 |
| John Leguizamo | Dr. Victor Clemente | ER Attending Physician | 2005–2006 |
| Kim Strauss | Dr. Ari | Anesthesiologist | 2005–2007 |
| Dahlia Salem | Dr. Jessica Albright | Surgical Chief Resident | 2005–2006 |
| J. P. Manoux | Dr. Dustin Crenshaw | Surgical Chief Resident, Surgical Attending | 2006–2008 |
| Busy Philipps | Dr. Hope Bobeck | ER Intern | 2006–2007 |
| Malaya Rivera Drew | Katey Alvaro | Medical Student | 2006–2007 |
| Gina Ravera | Dr. Bettina DeJesus | Radiologist | 2006–2008 |
| Julia Ling | Mae Lee Park | Medical Student | 2006–2007 |
| Marc Jablon | Dr. Larry Weston | ER Intern/Resident | 2007–2008 |
| Stanley Tucci | Dr. Kevin Moretti | Chief of Emergency Medicine | 2007, 2008 |
| Gil McKinney | Dr. Paul Grady | ER Intern/Resident | 2007–2009 |
| Steven Christopher Parker | Dr. Harold Zelinsky | Surgical Intern | 2007–2008 |
| Kari Matchett | Dr. Skye Wexler | Acting Chief of Emergency Medicine | 2007–2008 |
| Charles Esten | Dr. Barry Grossman | Orthopedic Surgeon | 2007–2008 |
| Anthony Starke | Dr. Craig | Orthopedic Surgeon | 2008 |
| Bresha Webb | Laverne St. John | Medical Student/ER Intern | 2008–2009 |
| Julia Jones | Kaya Montoya | Medical Student/ER Intern | 2008–2009 |
| Shiri Appleby | Dr. Daria Wade | ER Intern | 2008–2009 |
| Julian Morris | Dr. Andrew Wade | Surgical Intern | 2008–2009 |
| Victor Rasuk | Dr. Ryan Sánchez | ER Intern | 2008–2009 |
| Emily Rose | Dr. Tracy Martin | ER Intern | 2008–2009 |
| Sam Jones III | Dr. Charles "Chaz" Pratt, Jr. | ER Intern | 2005–2009 |
| Alexis Bledel | Dr. Julia Wise | ER Intern | 2009 |

### Firefighters, paramedics, police officers, and social workers

| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Rick Marzan | Camacho | Paramedic | 1994–1995 |
| Emily Wagner | Doris Pickman | Paramedic | 1994–2009 |
| Mike Genovese | Officer Al Grabarsky | Police Officer | 1995–2000 |
| Montae Russell | Dwight Zadro | Paramedic | 1995–2009 |
| Carlos Gómez | Raul Melendez | Paramedic | 1995–1996 |
| Ron Eldard | Ray "Shep" Shepard | Paramedic | 1995–1996 |
| Chad McKnight | Officer Wilson | Police Officer | 1995, 1996, 1999–2000, 2001–2004, 2006 |
| Lynn A. Henderson | Pamela Olbes | Paramedic | 1995–2009 |
| Scott Michael Campbell | Reilly Brown | EMT | 1996 |
| Brian Lester | Brian Dumar | Paramedic | 1996–2009 |
| Erica Gimpel | Adele Newman | Social Services Liaison | 1997–2003 |
| J.P. Hubbell | Lars Audia | EMT | 1997–1999 |
| Michele Morgan | Allison Beaumont | Paramedic | 1997–1998 |
| George Eads | Greg Powell | Paramedic | 1997–1998 |
| Ed Lauter | Captain Dannaker | Firefighter | 1998–2002 |
| Demetrius Navarro | Morales | Paramedic | 1998–2009 |
| Cress Williams | Officer Reggie Moore | Police Officer | 1998–2000, 2008 |
| Michelle Bonilla | Christine Harms | Paramedic | 1999–2009 |
| Joe Basile | Officer Tom Bennini | Police Officer | 2000 |
| David Roberson | Officer Durcy | Police Officer | 2000–2002 |
| Claudine Claudio | Silva | Paramedic | 2000–2001 |
| Lisa Vidal | Lieutenant Sandy Lopez | Firefighter | 2001–2004 |
| Julie Ann Emery | Niki Lumley | Paramedic | 2001–2003 |
| Daniel Dae Kim | Ken Sung | Social Worker | 2003–2004 |
| Louie Liberti | Tony Bardelli | Paramedic | 2003–2009 |
| Elliot Durant III | Anders | Paramedic | 2004, 2009 |
| Mädchen Amick | Wendall Meade | Social Worker | 2004–2005 |
| Bobby Nish | Officer Danny Yau | Police Officer | 2005–2006 |
| Tara Karsian | Liz Dade | Social Worker | 2005–2006, 2007, 2008–2009 |
| Eddie B. Smith | Officer Jones | Police Officer | 2005–2008 |
| Mary E. Kennedy | Officer Trudy Lange | Police Officer | 2006 |
| Louis Iacoviello | Officer Rovner | Police Officer | 2006 |
| Christopher Amitrano | Officer Hollis | Police Officer | 2006–2009 |
| Brendan Patrick Connor | Reidy | Paramedic | 2006–2008 |
| Vyto Ruginis | Wright | Paramedic | 2006–2007 |
| Joe Manganiello | Officer Litchman | Police Officer | 2007 |
| Sam Jones III | Charles "Chaz" Pratt, Jr. | EMT | 2005–2009 |
| Demetrius Grosse | Officer Newkirk | Police Officer | 2008–2009 |
| Justina Machado | Detective Claudia Diaz | Police Officer | 2009 |
| David Eigenberg | Detective Trent Mallory | Police Officer | 2009 |

### Family members

Key :
| Symbol | Meaning |
| ‡ | Another actor subsequently took over the role |
| † | Another actor previously held the role |
| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Christine Harnos | Jennifer "Jenn" Greene | Wife of Mark Greene | 1994–1998, 2001–2002 |
| Yvonne Zima ‡ | Rachel Greene | Daughter of Mark Greene and Jennifer Greene | 1994–2000 |
| Georgiana Tarjan ‡ | Helen Hathaway | Mother of Carol Hathaway | 1994–1995 |
| Ving Rhames | Walt Robbins | Brother-in-law of Peter Benton | 1994–1996 |
| Kathleen Wilhoite | Chloe Lewis | Sister of Susan Lewis | 1994–1996, 2002 |
| Beah Richards | Mae Benton | Mother of Peter Benton | 1995–2001 |
| Mike Genovese | Al Grabarsky | Boyfriend of Lydia Wright | 1995–2000 |
| Khandi Alexander | Jackie Robbins | Sister of Peter Benton | 1995–2001 |
| Christopher Richardson ‡ | Jesse Robbins | Nephew of Peter Benton | 1995 |
| Tamala Jones | Joanie Robbins | Niece of Peter Benton | 1995 |
| Mark Dakota Robinson | Steven Robbins | Nephew of Peter Benton | 1995 |
| Wolfgang Bodison ‡ | Al Boulet | Husband of Jeanie Boulet | 1995 |
| Valerie Perrine | Irene "Cookie" Lewis | Mother of Susan Lewis | 1995 |
| Michael Beach † | Al Boulet | Husband of Jeanie Boulet | 1995–1997 |
| Paul Dooley | Henry Lewis | Father of Susan Lewis | 1995–1996, 2004 |
| Piper Laurie | Sarah Ross | Mother of Doug Ross | 1995–1996 |
| James Farentino | Ray Ross | Father of Doug Ross | 1996 |
| Lisa Nicole Carson | Carla Reece | Mother of Reese Benton | 1996–2001 |
| John Aylward | Donald Anspaugh | Uncle of Simon Brenner | 1996–2008 |
| Rose Gregorio † | Helen Hathaway | Mother of Carol Hathaway | 1996–1999 |
| Frances Sternhagen | Millicent "Gamma" Carter | Grandmother of John Carter | 1997–2003 |
| Bonnie Bartlett | Ruth Greene | Mother of Mark Greene | 1997–1998 |
| John Cullum | David Greene | Father of Mark Greene | 1997–2000 |
| Jonathan Scarfe | Chase Carter | Cousin of John Carter | 1997–1998, 2001 |
| Trevor Morgan | Scott Anspaugh | Son of Donald Anspaugh | 1998 |
| George Plimpton | John Truman Carter, Sr. | Grandfather of John Carter | 1998–2001 |
| Taraji P. Henson | Patrice Robbins | Niece of Peter Benton | 1998 |
| Paul Freeman | Charles Corday | Father of Elizabeth Corday | 1998, 2001–2002 |
| Cress Williams | Reggie Moore | Boyfriend of Jeanie Boulet | 1998–2000, 2008 |
| Matthew Watkins | Reese Benton | Son of Peter Benton | 1999–2001, 2009 |
| Judy Parfitt | Isabelle Corday | Mother of Elizabeth Corday | 2000–2002 |
| Gwynyth Walsh | Barbara Knight | Mother of Lucy Knight | 2000 |
| Mark Valley | Richard Lockhart | Ex-husband of Abby Lockhart | 2000–2003 |
| Andrew McFarlane † | Jesse Robbins | Nephew of Peter Benton | 2000 |
| Sally Field | Maggie Wyczenski | Mother of Abby Lockhart | 2000–2006 |
| Nancy Kwan ‡ | Mrs. Chen | Mother of Jing-Mei Chen | 2000 |
| Sasha Turjak | Danijela Kovač | Wife of Luka Kovač | 2001 |
| Michael Gross | John "Jack" Carter, Jr. | Father of John Carter | 2001–2004 |
| Mary McDonnell | Eleanor Carter | Mother of John Carter | 2001 |
| Hallee Hirsh † | Rachel Greene | Daughter of Mark Greene and Jennifer Greene | 2001–2002, 2004, 2009 |
| Lisa Vidal | Sandy Lopez | Girlfriend of Kerry Weaver | 2001–2004 |
| Salome Violetta Haertel ‡ | Ella Greene | Daughter of Mark Greene and Elizabeth Corday | 2002 |
| Marcello Thedford | Leon | Foster brother of Greg Pratt | 2002–2003 |
| Tom Everett Scott | Eric Wyczenski | Brother of Abby Lockhart | 2002–2003 |
| George Kee Cheung ‡ | Mr. Chen | Father of Jing-Mei Chen | 2003–2004 |
| Kieu Chinh † | Mrs. Chen | Mother of Jing-Mei Chen | 2003 |
| Donal Logue | Chuck Martin | Husband of Susan Lewis | 2003–2005 |
| Oliver Davis ‡ | Alex Taggart | Son of Sam Taggart and Steve Curtis | 2003–2005 |
| Thandiwe Newton | Makemba "Kem" Likasu | Girlfriend of John Carter | 2003–2005, 2009 |
| Joy Bryant | Valerie Gallant | Sister of Michael Gallant | 2003–2004 |
| Shannon Wilcox | Connie Martin | Wife of Frank Martin | 2004 |
| Christine Young | Janie Martin | Daughter of Frank Martin and Connie Martin | 2004 |
| Cole Hauser ‡ | Steve Curtis | Ex-boyfriend of Sam Taggart | 2004 |
| Anupam Kher | Ajay Rasgotra | Father of Neela Rasgotra | 2004 |
| Kiron Kher | Mrs. Rasgotra | Mother of Neela Rasgotra | 2004 |
| Henry O † | Mr. Chen | Father of Jing-Mei Chen | 2004 |
| Frances Fisher | Helen Kingsley | Biological mother of Kerry Weaver | 2005 |
| Garret Dillahunt † | Steve Curtis | Ex-boyfriend of Sam Taggart | 2005–2006 |
| Danny Glover | Charles "Charlie" Pratt, Sr. | Father of Greg Pratt | 2005 |
| Sam Jones III | Charles "Chaz" Pratt, Jr. | Half-brother of Greg Pratt | 2005–2009 |
| Dominic Janes † | Alex Taggart | Son of Sam Taggart and Steve Curtis | 2005–2009 |
| Tina Lifford | Evelyn Pratt | Stepmother of Greg Pratt | 2005 |
| Cecily Lewis | Jocelyn Pratt | Half-sister of Greg Pratt | 2005 |
| Ernie Hudson | James Gallant | Father of Michael Gallant | 2006 |
| Sheryl Lee Ralph | Gloria Gallant | Mother of Michael Gallant | 2006 |
| Estelle Harris | Mrs. Markovic | Mother of Jerry Markovic | 2006 |
| Paula Malcolmson | Meg Riley | Mother of Sarah Riley | 2006–2007 |
| Chloe Greenfield | Sarah Riley | Daughter of Tony Gates | 2006–2009 |
| Aidan and Andrew Gonzales | Josip "Joe" Kovač | Son of Luka Kovač and Abby Lockhart | 2006–2009 |
| Fred Ward | Eddie Wyczenski | Father of Abby Lockhart | 2006–2007 |
| Lois Smith | Gracie | Grandmother of Sam Taggart | 2007 |
| Stacy Keach | Mike Gates | Father of Tony Gates | 2007 |
| Rosalee Mayeux | Jacey Barnett | Mother of Ray Barnett | 2007 |
| Zoran Radanovich | Niko Kovač | Brother of Luka Kovač | 2007 |
| Oscar Blanco | Carlos Moore | Son of Jeanie Boulet | 2008 |
| Rebecca Hazlewood | Jaspreet | Cousin of Neela Rasgotra | 2008 |
| Courtney B. Vance | Russell Banfield | Husband of Cate Banfield | 2008–2009 |
| Ellaraino | Mary Banfield | Mother-in-law of Cate Banfield | 2008 |
| Daylon Adkison | Daryl Banfield | Son of Cate Banfield and Russell Banfield | 2008 |
| Kasey Mahaffy | Johnny Morris | Cousin of Archie Morris | 2009 |
| Shannon Woodward | Kelly Taggart | Sister of Sam Taggart | 2009 |
| Kristolyn Lloyd | Laura | Niece of Cate Banfield | 2009 |
| Amy Madigan | Mary Taggart | Mother of Sam Taggart | 2009 |

### Notable patients

| Actor/Actress | Character Name | Character Position | Years of Appearance |
| Rosemary Clooney | Mary "Madame X" Cavanaugh | Former singer who suffers from Alzheimer's disease | 1994 |
| Kevin Michael Richardson | Patrick | Mentally disabled boy who occasionally wanders into the ER | 1994 |
| Colleen Flynn | Jodi O'Brien | Patient who died during childbirth under Dr. Mark Greene's care | 1995 |
| Mary Mara | Loretta Sweet | Sympathetic, down-and-out prostitute and single mother who has cervical cancer | 1995–1996 |
| Kirsten Dunst | Charlene "Charlie" Chiemingo | Child prostitute who was being cared for by Dr. Doug Ross | 1996–1997 |
| Sam Vlahos | Pablo | Homeless man who sought care from County's medical staff | 1997–2003 |
| David Krumholtz | Paul Sobriki | Schizophrenic patient who in a psychotic break stabbed both Dr. John Carter and Lucy Knight, the wounds leaving Carter injured and with life-long kidney problems and eventually resulted in Lucy's death | 2000, 2002 |
| James Cromwell | Bishop Lionel Stewart | Catholic bishop who helped Dr. Luka Kovač with his guilt about the death of his family | 2001 |
| Ray Liotta | Charlie Metcalf | Alcoholic ex-con who comes to the ER with a cirrhosis-related illnesses | 2004 |
| Red Buttons | Jules "Ruby" Rubadoux | Patient (whose wife died after becoming part of a medical study at Dr. Carter's suggestion) with heart problems | 1995–1996, 2005 |
| James Woods | Dr. Nate Lennox | Former biochemistry professor with ALS disease | 2006 |
| Forest Whitaker | Curtis Ames | Patient who sued Dr. Kovač for malpractice after suffering from a paralyzing stroke while under his care for pneumonia | 2006–2007 |