Lou Diamond Phillips’ big break came with the starring role in La Bamba (1987) in which he played early rocker Ritchie Valens. Prior to his cinematic breakthrough, he starred in the Miami Vice episode “Red Tape” portraying detective Bobby Diaz.
In 1988, Phillips co-starred with Edward James Olmos in the inner-city high school drama Stand and Deliver, in a role for which he was nominated for the Golden Globe Award for Best Supporting Actor – Motion Picture and won the Independent Spirit Award for Best Supporting Male. He plays Angel David Guzman, a cholo gangster who is inspired by his math teacher, Jaime Escalante, to excel at calculus. Working to master the subject, he develops a friendship with his teacher.
In 1988 Phillips co-starred with Emilio Estevez and Kiefer Sutherland in the Western film Young Guns, in which he plays Jose Chavez y Chavez, a historical Old West outlaw.
In 1990, he revisited the role of Jose Chavez y Chavez in Young Guns II.
In the mid-1990s, Phillips was a vocalist with the Los Angeles-based rock group The Pipefitters.
In 1993, Phillips was among the guests on the Randy Travis television special Wind in the Wire.
In 1996, Phillips made his Broadway debut as the King in Richard Rodgers and Oscar Hammerstein II’s The King and I. Phillips won a Theatre World Award, and was nominated for both a Tony Award and a Drama Desk Award for his performance.
In 1998, he starred as Cisco, the counterpart of the main character Melvin Smiley (played by Mark Wahlberg) in the comedy-action film The Big Hit.
He later featured a minor role in the TV sitcom George Lopez (2002–2004) as George Lopez’s half-brother. He also played a role in the first season of the TV series 24 as secret government agent Mark DeSalvo, opposite former Young Guns star Kiefer Sutherland. Phillips played the recurring role of FBI agent Ian Edgerton in the television series Numb3rs. Edgerton is an FBI tracker and sniper who works as an instructor at Quantico FBI Academy when he is not working a case in the field.
Phillips won the second season of the NBC reality series, I’m a Celebrity…Get Me Out of Here!, over pro wrestler Torrie Wilson.
Phillips currently hosts the weekly series An Officer and a Movie on The Military Channel. This series features various theatrical World War II dramas, with discussion breaks during the film in which Phillips interviews members of the US military and intelligence communities about details of the events that inspired each film.
In 2003, he starred in a cameo role with Harrison Ford in an action-comedy film Hollywood Homicide.
On September 11, 2007, Phillips joined the touring troupe for Lerner and Loewe’s Camelot in the role of King Arthur.
Phillips had a recurring role as Colonel Telford in the Stargate Universe television series during its two-season run on the SyFy channel 2009–2011. He played the would-be commander of the Destiny expedition, who is left behind when an accident launches an unsuspecting crew into deep space. The commander works from Earth to bring the crew home, often coming into conflict with the shipborne command characters.
In January 2012, he was one of eight celebrities participating in the Food Network reality series Rachael vs. Guy: Celebrity Cook-Off. On January 29, 2012, he was announced as the winner with a Zagat score of 28 out of 30, thereby winning $50,000 for his charity.
In June 2012, Phillips began co-starring in the television series Longmire, about a modern-day sheriff played by Robert Taylor. Phillips played Henry Standing Bear, a Native American, who is Longmire’s best friend, often helping him with cases and in dealing with the reservation police who do not respect or like outsiders, especially other law enforcement.
In December 2012, he was featured in Imagine Dragons’ music video for “Radioactive”, which went on to eclipse 1 billion views on YouTube.
In February 2013, Phillips appeared as star of the comedy short film Lucy in the Sky with Diamond, playing a hyperbolized version of himself known as the elusive and mysterious LDP—a renegade, spirit guide, and life coach who attempts to help John (John Patrick Jordan) get over a particularly disconcerting ex-girlfriend. The award-winning short was written and directed by Joey Boukadakis.
In July 2014, he replaced the injured Jason Scott Lee in Opera Australia’s Melbourne production of The King and I, reprising his role as the King of Siam, playing opposite Lisa McCune as Anna Leonowens.
In 2015, he also guest-starred in The Wiggles Rock and Roll PreSchool DVD and made guest appearances on their TV program on ABC.’
In 2016, Phillips portrayed serial killer Richard Ramirez in The Night Stalker.
In 2023, Phillips competed in season nine of The Masked Singer as “Mantis”. After being spared by Robin Thicke ringing the Ding Dong Keep It On Bell on “WB Movie Night”, he was eliminated during the “Battle of the Saved” alongside Keenan Allen as “Gargoyle”. Phillips also mentioned that he did the competition for his daughter Indigo and her friend Fluffy.
Phillips starred in four episodes of the radio series The Twilight Zone: Vol. 1, “A Kind of a Stopwatch”; Vol. 3, “The Parallel; Vol. 10, “Miniature”; and Vol. 12, “Long Live Walter Jameson”.
Phillips co-wrote the screenplay for Trespasses and HBO’s Dangerous Touch, and wrote the Miramax feature Ambition. In 2019 Aethon Books announced that it would be publishing Phillips’ debut novel, Tinderbox: Soldier of Indira, a science fiction retelling of the Hans Christian Andersen story of the same name, illustrated by his wife, Yvonne.