Thomas Mark Harmon (born September 2, 1951) is an American actor, producer and director. He is known for playing the lead role of Leroy Jethro Gibbs on NCIS (2003-2021), a role which has earned him six nominations at the People's Choice Awards including a win for Favorite TV Crime Drama Actor in 2017. Since 2008, he has also been a producer and executive producer of the show as well as its' spinoff series NCIS: New Orleans. His character of NCIS special agent Leroy Jethro Gibbs was introduced in a guest starring role in two episodes of JAG, and continued on the spinoff show NCIS.
He had a recurring role as Secret Service special agent Simon Donovan in a four-episode story arc in The West Wing in 2002, for which he received an Emmy Award nomination.
One of his first national TV appearances (other than as an athlete) was in a commercial for Kellogg's Product 19 cereal with his father, Tom Harmon, its longstanding TV spokesman. Thanks to his sister Kristin's in-laws, Ozzie and Harriet Nelson, he landed his first job as an actor in an episode of Ozzie's Girls.
He has been starring in television and film since the mid-1970s, after a career as a collegiate football player with the UCLA Bruins.
He's been married to actress Pam Dawber since 1987 and they have 2 sons. His son, actor Sean Harmon, had a recurring role as a young Leeroy Jethro Gibbs on NCIS.
Recent movies
| # | Name | Character | Rating |
|---|---|---|---|
| 1 | Freakier Friday (2025) | Ryan | 9 |
| 2 | Certain Prey (2011) | Lucas Davenport | 2 |
| 3 | Justice League: Crisis on Two Earths (2010) | Superman (voice) | 7.2 |
| 4 | Weather Girl (2009) | Dale | 5.8 |
| 5 | Chasing Liberty (2004) | James Foster | 6.3 |
| 6 | Freaky Friday (2003) | Ryan | 6.3 |
| 7 | Local Boys (2002) | Jim Wesley | 7 |
| 8 | And Never Let Her Go (2001) | Thomas Capano | - |
| 9 | Crossfire Trail (2001) | Bruce Barkow | - |
| 10 | Fear and Loathing in Las Vegas (1998) | Magazine Reporter | 7.8 |
| 11 | The Last Supper (1995) | Dominant Male | 7 |
| 12 | Magic in the Water (1995) | Jack Black | - |
| 13 | Wyatt Earp (1994) | Sheriff Johnny Behan | 6.6 |
| 14 | Natural Born Killers (1994) | Mickey Knox in TV | 7.3 |
| 15 | Dillinger (1991) | John Dillinger | - |
| 16 | Fourth Story (1991) | David Shepard | - |
| 17 | Worth Winning (1989) | Taylor Worth | - |
| 18 | Sweet Bird of Youth (1989) | Chance Wayne | - |
| 19 | Stealing Home (1988) | Billy Wyatt | - |
| 20 | The Presidio (1988) | Jay Austin | 5 |
| 21 | Summer School (1987) | Mr. Freddy Shoop | 5.6 |
| 22 | Dear America: Letters Home from Vietnam (1987) | (voice) | - |
| 23 | The Deliberate Stranger (1986) | Ted Bundy | - |
| 24 | Beyond the Poseidon Adventure (1979) | Larry Simpson | 7 |
| 25 | Eleanor and Franklin: The White House Years (1977) | Robert Dunlap | 6 |

