| Year | Title | Role | Notes | Reference |
| 1969 | The Survivors | Mike | Episode: "Chapter Seven" | |
| Ironside | Danny Goodson | Episode: "Stolen on Demand" | |
| 1970 | Adam-12 | Tim Richmond | Episode: "Log 24 A Rare Occasion" | |
| Bonanza | Billy Burgess | Episode: "The Law and Billy Burgess" | |
| Marcus Welby, M.D. | Michael Ambrose | Episode: "Fun and Games and Michael Ambrose" | |
| Medical Center | Rick Lambert | Episode: "His Brother's Keeper" | |
| The Mod Squad | Brad Johnson | Episode: "The Loser" | |
| The F.B.I. | Larry Wentworth | Episode: "Fatal Impostor" | |
| 1970–74 | The Partridge Family | Keith Partridge | 96 episodes | |
| 1978 | Police Story | Officer Dan Shay | Episode: "A Chance to Live" | |
| 1978–79 | David Cassidy: Man Undercover | Officer Dan Shay | 10 episodes; also composer of theme music | |
| 1980 | The Love Boat | Ted Harmes | 1 episode | |
| The Night the City Screamed | David Greeley | TV movie | |
| 1980/83 | Fantasy Island | Jeremy Todd / Danny Collier | 2 episodes | |
| 1982 | Matt Houston | John Gordon Boyd | Episode: "Joey's Here" | |
| 1983 | Parade of Stars | George M. Cohan | TV movie | |
| Tales of the Unexpected | Donald / David | Episode: "Heir Presumptuous" | |
| 1988 | Alfred Hitchcock Presents | Joey Mitchell | Episode: "Career Move" | |
| 1990 | Instant Karma | Reno | | |
| The Spirit of '76 | Adam-11 | | |
| 1991 | Blossom | Himself | Episode: "A Rockumentary" | |
| The Flash | Sam Scudder/Mirror Master | Episode: "Done with Mirrors" | |
| 1992 | The Ben Stiller Show | David Cassidy | Episode: "With Flea" | |
| 1993 | Ein Schloß am Wörthersee | Patrick Riley | Episode: "Falsches Spiel mit Patrick" | |
| 1995 | The John Larroquette Show | Jefferson Kelly | Episode: "Wrestling Matches"; also composer of theme music | |
| 2003 | Malcolm in the Middle | Boone Vincent | Episode: "Vegas" | |
| The Agency | Everett Price | Episode: "War, Inc." | |
| I Love the '70s | Himself | | |
| 2004 | Kim Possible | Roland Pond (voice) | Episode: "Oh Boyz" | |
| 2005 | Less than Perfect | Vince | Episode: "Playhouse" | |
| Popstar | Grant | | |
| 2009 | Ruby & The Rockits | David Gallagher | 10 episodes | |
| 2011 | Celebrity Apprentice | Himself/contestant | 2 episodes | |
| 2013 | CSI: Crime Scene Investigation | Peter Coe | Episode: "Last Woman Standing" | |
| 2018 | David Cassidy: The Last Session | Himself | TV special; posthumous release | |