He was born in Washington, D.C. and began studying piano at the age of nine, and showed an aptitude for music by learning to play several different instruments, including the banjo and acoustic and bass guitars. Tork attended Carleton College but dropped out and moved to New York City, where he became part of the folk music scene in Greenwich Village during the first half of the 1960s. While there he befriended other up and coming musicians such as Stephen Stills, and after both moved to the Los Angeles area Stills suggested Tork audition for a new television series about four pop-rock musicians. Tork got the job and became one of the four members of The Monkees, who ended up being both characters in a television sitcom and a band in their own right.

Tork was a proficient musician, and though the group did not play their own instruments on their first two albums, after that point he played keyboards, bass guitar, banjo, and other instruments on their recordings. He also wrote the closing theme song of the second season of The Monkees, "For Pete's Sake." On the television show, he was relegated to playing the dummy even though he was actually an intelligent, literate person.

After two years of the show, six albums, a movie, and a television special, Tork had had enough and quit the group, striking out on his own with a group called “Release.” This new band never achieved success, and problems with drugs including alcohol led to his leaving show business entirely for a few years while he taught school and coached basketball. Finally in 1980 he quit drinking and the next year gave up drugs, and in 1986 he rejoined fellow-Monkees Davy Jones and Micky Dolenz for a 20th anniversary reunion tour. Since then he has intermittently toured with his former bandmates and also played with his own bands The Peter Tork Project and Shoe Suede Blues as well as in solo performances and with touring partner James Lee Stanley.