Born 28 September 1951 in Rome, daughter of a pediatrician, Silvia Dionisio made her debut in the world of cinema when she was 14 years old in the movie Darling (1965, John Schlesinger).

In 1967 she won the beauty contest Miss Teenager. After a few "musicarelli" movies, where she met director Ruggero Deodato (whom she married december 5, 1971), she got her first main role in the 1970 movie "A Girl Called Jules" (La ragazza di nome Giulio). She had a son (Saverio Deodato Dionisio, later actor), then divorced in 1979.