Growing up in Munich, Bavaria, Kaufmann became a ballerina at the Munich Opera. She began her film career at the age of seven in The White Horse Inn (1952) and appeared as a lead Actress in Der Schweigende Engel the same year, but gained big attention with Rose-Girl Resli in 1954. She achived international recognition when she starred with Steve Reeves in The Last Days of Pompeii (1959) and with Kirk Douglas in Town Without Pity (1961). The following year she appeared in Escape from East Berlin (1962).

At age 18 in 1963, Kaufmann married Tony Curtis, whom she had met during the filming of Taras Bulba (also 1962). They had two daughters, Alexandra (born 19 July 1964) and Allegra (born 11 July 1966). The couple divorced in 1968. Kaufmann married three more times: television Director Achim Lenz (1974–76), musician and actor Reno Eckstein (1979-1982) and Illustrator Klaus Zey (1997-2011). On German television, Kaufmann admitted to having an affair with Warren Beatty.

Kaufmannn resumed her career, which she had interrupted during her marriage, after her divorce with Tony Curtis, notably with supporting roles in the Rainer Werner Fassbinder films Lili Marleen and Lola. She often worked with German Director Helmut Dietl, for Example in the satirical television series Monaco Franze – Der ewige Stenz. In 1987, she played a glamerous tattoo Artist in the cult classic Bagdad Cafe, an offbeat comedy set in a desolate truck stop cafe and motel in the Mojave Desert. Her last role was Aunt Polly in the American film Tom Sawyer & Huckleberry Finn (2014), co-starring Jake T. Austin and Val Kilmer.

Kaufmann enjoyed travelling. She moved from one place to another frequently—a pattern that she believed she had inherited from her Circassian forefathers. She spoke three languages: German, English, and French.

Kaufmann died on 28 March 2017 in Munich from with leukaemia at the age of 72. She was only diagnosed with leukemia a few days before her death.