| Year | Title | Role | Notes |
| 1983 | St. Elsewhere | Sandy Burns | 3 episodes |
| Remington Steele | Barbara Troy Dannon | Episode: "Altared Steele" |
| Scarecrow and Mrs. King | Penny | Episode: "Always Look a Gift Horse in the Mouth" |
| 1983–1984 | The Paper Chase | Connie Lehman | 8 episodes |
| 1984 | Hill Street Blues | Officer Clara Pilksy | 6 episodes |
| Something About Amelia | Mrs. Hall | Television movie |
| Crazy Like a Fox | Julie Floyd | Pilot episode |
| 1985 | Hometown | Mary Newell Abbott | 10 episodes |
| 1986 | The Right of the People | Alicia | Television movie |
| The Christmas Gift | Susan |
| 1987 | I'll Take Manhattan | Nina Stern |
| The Three Kings | Dr. Paula Bolet |
| 1988 | American Playhouse | Susan Glaspell | Episode: "Journey Into Genius" |
| 1989 | Spooner | Gail Archer | Television movie |
| 1990–1991 | Equal Justice | Linda Bauer | 22 episodes |
| 1993 | Big Wave Dave's | Karen Fisher | 6 episodes |
| 1994 | Monty | Nickerson | Episode: "Wild, Wild Willy and His O.K. Corral" |
| Law & Order | Janet Rudman | Episode: "Censure" |
| ABC Afterschool Specials | Mary Reed | Episode: "Boys Will Be Boys" |
| Law | Karen Gershon-woo | Episode: "Whose San Andreas Fault Is It, Anyways?" |
| Without Warning | Dr. Caroline Jaffe | Television movie |
| 1995 | Picket Fences | Janice Neiman | Episode: "Heroes and Villains" |
| 1995–1999 | Party of Five | Helene Thompson | 3 episodes |
| 1996 | Touched by an Angel | Bonnie Bell | Episode: "Out of the Darkness" |
| ABC Afterschool Specials | Nancy Gallagher | Episode: "Educating Mom" |
| Apollo 11 | Jan Armstrong | Television movie |
| 1996–1997 | Cybill | Holly | 5 episodes |
| Frasier | Maureen Cutler | 2 episodes |
| 1997 | The Practice | Pamela Boyd |
| 1999 | Felicity | Carol Anderson | 5 episodes |
| 2000–2006 | Malcolm in the Middle | Lois | 151 episodesAmerican Comedy Award for Funniest Female Performer in a Television SeriesSatellite Award for Best Actress – Television Series Musical or ComedyTelevision Critics Association Award for Individual Achievement in Comedy (2000–01)Nominated—Golden Globe Award for Best Actress – Television Series Musical or Comedy (2001–03)Nominated—Primetime Emmy Award for Outstanding Lead Actress in a Comedy Series (2000–06)Nominated—Satellite Award for Best Actress – Television Series Musical or ComedyNominated—Screen Actors Guild Award for Outstanding Performance by a Female Actor in a Comedy Series (2001, 2003)Nominated—Teen Choice Award for Choice TV Actress – ComedyNominated—Viewers for Quality Television Award for Best Actress in a Quality Comedy Series |
| 2001–present | The Simpsons | Judge Constance Harm (voice) | 10 episodes |
| 2006–2007 | Help Me Help You | Anne Hoffman | 6 episodes |
| 2008–2009 | Raising the Bar | Judge Trudy Kessler | 23 episodes |
| 2010 | Reviving Ophelia | Marie Jones | Television movie |
| 2011 | Wilfred | Beth | Episode: "Pride" |
| 2011–2012 | Whitney | Candi | 3 episodes |
| 2012–2013 | The Middle | Sandy Armwood | 2 episodes |
| 2012–2015 | Jake and the Never Land Pirates | Red Jessica (voice) | 12 episodes |
| 2013 | Law & Order: Special Victims Unit | Pam James | Episode: "Beautiful Frame" |
| 2014 | Phineas and Ferb | Denise (voice) | Episode: "Lost in Danville/The Inator Method" |
| Us & Them | Pam | 7 episodes |
| 2014–2017 | Playing House | Gwen Crawford | 7 episodes |
| 2015 | The McCarthys | Eileen | Episode: "Sister Act" |
| Big Time in Hollywood, FL | Dr. Moore | 2 episodes |
| Penn Zero: Part-Time Hero | Coach Jackie (voice) | Episode: "Ultrahyperball" |
| 2016 | The Big Bang Theory | Dr. Gallo | Episode: "The Sales Call Sublimation" |
| Cooper Barrett's Guide to Surviving Life | Cindy Barrett | Episode: "How to Survive Your Parents' Visit" |
| 2018 | Animals. | Judge (voice) | Episode: "The Trial" |
