Robbins was born in West Covina, California, and raised in New York City. He is the son of Mary Cecelia (née Bledsoe; c. 1933–2011), an Actress, and Gilbert Lee Robbins (1931–2011), a musician, folk singer, actor, and former manager of The Gaslight Cafe. Robbins has two sisters, Adele and Gabrielle, and a brother, David. He was raised Catholic.

He moved to Greenwich Village with his family at a young age, while his Father pursued a career as a member of the folk music group, The Highwaymen. Robbins started performing in theater at age twelve and joined the drama club at Stuyvesant High School (Class of 1976). He spent two years at SUNY Plattsburgh and then returned to California to study at the UCLA Film School, graduating with a Bachelor of Arts degree in Drama in 1981.

Robbins's acting career began at Theater for the New City, where he spent his teenage years in their Annual Summer Street Theater and also played the title role in a musical adaptation of Antoine de Saint-Exupéry's The Little Prince. After graduation from college in 1981, Robbins founded the Actors' Gang, an experimental theater group, in Los Angeles with actor friends from his college softball team (including John Cusack).

In 1982, he appeared as domestic terrorist Andrew Reinhardt in three episodes of the television program St. Elsewhere. In 1985, he guest-starred in the second episode of the television series Moonlighting, "Gunfight at the So-So Corral". He also took small parts in films, such as the role of frat animal "Mother" in Fraternity Vacation (1985) and Lt Sam "Merlin" Wells in the fighter pilot film Top Gun (1986). He appeared on The Love Boat, as a young version of one of the characters in retrospection about the Second World War. His breakthrough role was as pitcher Ebby Calvin "Nuke" LaLoosh in the 1988 baseball film Bull Durham, in which he co-starred with Susan Sarandon and Kevin Costner.

In 1988, Robbins entered into a relationship with Actress Susan Sarandon, whom he met on the set of Bull Durham. They have two sons: John "Jack" Henry (born May 15, 1989) and Miles Guthrie (born May 4, 1992). Robbins, like Sarandon, is a lapsed Catholic, and they both share liberal political views. The end of Robbins' relationship with Sarandon was announced in late December 2009.

He received critical acclaim and won the Best Actor Award at Cannes for his starring role as an amoral film executive in Robert Altman's 1992 film The Player. He made his directorial and screenwriting debut with 1992's Bob Roberts, a mockumentary about a right-wing senatorial candidate. Robbins then starred alongside Morgan Freeman in the critically acclaimed The Shawshank Redemption (1994), which was based on Stephen King's novella.

Robbins is an avid baseball and ice hockey fan. He supports the New York Mets and the New York Rangers and frequently attends games. In 1995 Robbins did a series of promos for MSG Network advertising upcoming Rangers games, and has narrated a documentary on the 1969 Mets for SNY.

Robbins supported Ralph Nader's 2000 presidential campaign and appeared on stage in character as Bob Roberts during the "Nader Rocks the Garden" rally at Madison Square Garden. In December 2007, Robbins campaigned for Senator John Edwards in the 2008 U.S. presidential election. He delivered a speech critical of Hillary Clinton and the DLC while introducing Bernie Sanders at a 2016 campaign stop.

He publicly opposed the 2003 invasion of Iraq. In 2003, a 15th anniversary celebration of Bull Durham at the National Baseball Hall of Fame was canceled by Hall of Fame President Dale Petroskey. Petroskey, who was on the White House staff during the Reagan administration, told Robbins that his stance helped to "undermine the U.S. position, which could put our troops in even more danger." Durham co-star Kevin Costner defended Robbins and Sarandon, saying, "I think Tim and Susan's courage is the type of courage that makes our democracy work. Pulling back this invite is against the whole principle about what we fight for and profess to be about." Robbins later said that Kevin Costner, Clint Eastwood, and Jack Valenti were the only major Hollywood figures that stood up for his free speech rights in this case and noted that all three men are either Republicans or very conservative Democrats, adding that he felt there could be Common ground between individuals with different political beliefs.

In early 2006, Robbins directed an adaptation of George Orwell's novel 1984, written by Michael Gene Sullivan of the Tony Award-winning San Francisco Mime Troupe. The show opened at Actors' Gang, at their new location at The Ivy Substation in Culver City, California. In addition to venues around the United States, it has played in Athens, Greece, the Melbourne International Festival in Australia and the Hong Kong Arts Festival. Robbins is considering adapting the play into a film version.

In 2008, Robbins appeared in The Lucky Ones, with co-star Rachel McAdams as well as City Of Ember. Robbins next film role was as Senator Hammond, the disapproving Father of the film's villain Hector Hammond, in the 2011 superhero film Green Lantern.

In 2010 Robbins released the album Tim Robbins & The Rogues Gallery Band, a collection of songs written over the course of 25 years that he ultimately took on a world tour. He was originally offered the chance to record an album in 1992 after the success of his film Bob Roberts, but he declined because he had "too much respect for the process", having seen his Father work so hard as a musician, and because he felt he had nothing to say at the time.

Robbins directed two episodes of the HBO series Treme. The series follows the interconnected lives of a group of New Orleanians in the wake of Hurricane Katrina. He helmed the episodes "Everything I Do Gonh Be Funky" in Season 2 (2011) and "Promised Land" in Season 3 (2012). Robbins became interested in the show while staying in New Orleans during the filming of Green Lantern. "I had the unique experience of watching Treme with locals. It resonated for me immediately, and it resonated for them as well, because they have seen their town get misinterpreted and represented in ridiculous ways," he told The Times-Picayune in 2011. “Something about this show was different for them. I appreciated that. I loved the writing and the actors. I loved the environment it’s set in. I watched the whole first season in New Orleans, and got in touch with David Simon and said, ‘If you guys need a Director next year, I’d be happy to do an episode.'"

In 2013, he was a member of the jury at the 63rd Berlin International Film Festival.

In 2015, he played Secretary of State, Walter Larson in the HBO comedy The Brink, and since 2018 he has played Greg Boatwright in Alan Balls' drama series Here and Now.