Pontecorvo was born on 22 August 1913 in Marina di Pisa, the fourth of eight children of Massimo Pontecorvo and his wife Maria . His older brother Guido, who was born in 1907, became a geneticist. His brother Paolo, who was born in 1909, became an engineer who worked on radar during World War II. His older sister Giuliana was born in 1911. His younger brother Gillo was born in 1919, and is best known as the director of "The Battle of Algiers". He also had two younger sisters; Laura, who was born in 1921, and Anna, who was born in 1924, and a younger brother Giovanni, who was born in 1926. His family was a wealthy family; Massimo owned three textile factories employing over 1,000 people. The family was Jewish and non-observant, from Rome on his father's side and from Mantua - on the mother's. His grandfather on maternal side, Arrigo Maroni (1852–1924), born in Mantua, was director of the Fatebenefratelli Hospital in Milan; the mother's cousin was a notable zoologist Elisa Gurrieri-Norsa (1868-1939).