Margherita Sarfatti (1880-1961) was an Italian journalist, art critic, patron, collector, socialite, and one of Benito Mussolini's mistresses.

Born Margherita Grassini, the daughter of a wealthy Jewish lawyer, she grew up in a palazzo situated at the Canale Grande in Venice and was educated by private tutors. However, she was soon attracted by socialist ideas and escaped her parents' home at age 18 by marrying Cesare Sarfatti, a lawyer from Padua many years her senior. In 1902 the couple moved to Milan.

In 1911 Margherita Sarfatti met, and started an affair with, Benito Mussolini. As a highly educated and intellectual woman, she played a significant role in the rise of fascism, only to be discarded when her lover turned to anti-Semitism, unable to credit a Jewish woman as his collaborator in the forging of a new, revolutionary ideology. In 1938, Sarfatti left Italy for Argentina. After the war, in 1947, Sarfatti returned to her home country and once again became an influential force in Italian art.

While Mussolini was racist toward Africans and Asians, Fascism was not inherently anti-Semitic. But when his conquest of Abyssinia drew opprobium from the League of Nations, he found solace only from Hitler and the like-minded. To curry favour with Hitler, the race laws were passed in 1938 and Sarfatti necessarily had to leave Mussolini's bed.

Actress Susan Sarandon portrayed Sarfatti in the 1999 movie Cradle Will Rock which was written and directed by Sarandon's longtime companion, Tim Robbins. Sarandon discussed her role, saying: