Ekberg was born in 1931 in Malmö, Skåne, the oldest girl and the sixth of eight children. In her teens, she worked as a fashion model. In 1950, Ekberg entered the Miss Malmö competition at her mother's urging, leading to the Miss Sweden contest, which she won. She consequently went to America to compete for Miss Universe in the United States despite not speaking English. Although she did not win Miss Universe, as one of six finalists she did earn a starlet's contract with Universal Studios, as was the rule at the time. In America, Ekberg met Howard Hughes.

As a starlet at Universal, Ekberg received lessons in drama, elocution, dancing, horse-riding and fencing. Ekberg skipped many of the lessons, restricting herself to horse riding in the Hollywood hills.

Bob Hope joked that her parents had received the Nobel Prize for architecture as she was touring with him and William Holden to entertain U.S. troops in 1954.

Federico Fellini gave Ekberg her greatest role in La dolce vita (1960), in which she played the unattainable "dream woman" opposite Marcello Mastroianni; then Boccaccio '70 in 1960, a movie that also featured Sophia Loren. Fellini would call her back for two other films: I clowns (1972), and Intervista (1987), where she played herself in a reunion scene with Mastroianni. La Dolce Vita was a sensational success, and Anita Ekberg's uninhibited cavorting in Rome's Trevi Fountain remains one of the most celebrated images in film history.

She once said, "It was I who made Fellini famous, not the other way around."