Santilli was born in Spigno Saturnia, Lazio. She started modelling and acting in theatre while studying at the Sapienza University of Rome. In 1971, she appeared in an issue of the adult magazine "Playmen". She acted in twelve movies between 1971 and 1974. Her final movie role was in the comedy "Unbelievable Adventures of Italians in Russia" (1974), shot in the Soviet Union.