He was born in Ovalle on 23 September 1894, the son of Primitivo Pizarro and Clotilde Cabezas.[1] He married Matilde Aracena.[1]
He studied at the Liceo de La Serena and later at the local School of Mines, where he graduated as a mining engineer.[1] Professionally, he worked as an administrator and engineer for several mining companies, including Disputada Las Condes, Compañía Gatico, and Compañía Tocopilla (Mina Cocinera).[1] In parallel, he dedicated part of his life to agriculture, managing and cultivating the estates Tuqui and La Feria in his native Ovalle.[1]
Pizarro was first affiliated with the Democratic Party in 1945 and later joined the Liberal Party in 1953.[1] He was elected Deputy for the 4th Departmental Group (La Serena, Coquimbo, Elqui, Ovalle, Combarbalá and Illapel) for three consecutive terms: 1945–1949, 1949–1953, and 1953–1954.[1] He died in office in 1954 and was replaced by Máximo Corral Garrido, who took office on 22 March 1955.[1]
Throughout his parliamentary career, he sat on the Standing Committee on Industry—of which he served as president during his first term—and also participated in the Committees on Foreign Affairs and on Roads and Public Works.[1] Beyond Congress, he served as delegate of the Ovalle Association before the National Mining Society (SONAMI) and was a member of the National Agriculture Society (SNA).[1]
He died on 6 September 1954, at the age of 59.[1]