Zanetta Farussi, or Maria Giovanna Farussi (Venice 27 August 1707 – Dresden 29 November 1776), was an Italian actress, opera singer and composer. She was the mother of Giacomo Casanova.
Fanussi was the daughter of a shoe maker and married on 27 February 1724 to the actor Gaetano Casanova. The marriage was conducted against the will of her parents, who were afraid that she would join her spouse's profession, which she also did. After her debut at Teatro San Samuele in Venice, she performed in 1726–1728 at Kings Theatre in London, where she made a success. King George II of Great Britain was rumoured to have been the father of her son Franscisco (born 1727) - it is unknown whether this was true, or whether the rumour was encouraged for publicity's sake. She was again active at Teatro San Samuele upon her return to Venice. Carlo Goldoni wrote the play La pupilla for her. She was active at the Italian theatre at the Russian Imperial court in 1735, and at the Italian court theatre in Dresden in 1737, where she was followed by two of her children; Maria Magdalena and Giovanni. Maria Magdalena was to marry the court organist Peter August, and Giovanni became a teacher of painting at the arts academy. On 6 November 1748, her own composition was performed in Warsaw. She retired with a pension to Prague in 1756, where she remained during the Seven year's war. She returned to Dresden after the war.