Born in Santiago in the province of Veraguas, the sixth of twelve children. He was educated at the local Juan Demóstenes Arosemena school and won a scholarship to the military academy in San Salvador. He graduated with a commission as a second lieutenant. He joined the Panamanian army, the National Guard (Guardia Nacional), in 1952. He was promoted to captain in 1956 and studied further at the School of the Americas.
He had reached the rank of lieutenant colonel by 1966 and in 1968 he and colonel Boris Martínez led a successful coup d'etat against the democratically-elected president, Arnulfo Arias. In the internal power struggle that followed Torrijos emerged victorious - he exiled Martínez in 1969, made himself a brigadier general and survived an attempted coup from his junior officers. Torrijos further consolidated his power by taking authoritarian measures such as persecuting leaders of student and labor groups, dissolving all political parties and the legislature, closing down independent media outlets, and conducting a ruthless anti-guerrilla campaign in Western Panama. Under these conditions, the regime called for controlled election of an assembly with a single opposition member, which approved a Constitution that granted Torrijos absolute civil and military powers in 1972.
Torrijos instituted a range of social and economic reforms (military socialism) to improve the lot of the poor, redistributed agricultural land and persecuted the richest and most powerful families in the country, as well as independent student and labor leaders. The reforms were accompanied by an ambitious public works program, financed by foreign banks, and plagued by corruption and nepotism, which turned Panama into one of the countries with highest per capita public indebtedness. He was intolerant of political opposition however and many opponents were imprisoned, exiled or even killed. He also negotiated the new Panama Canal Treaty and Neutrality Treaty with Jimmy Carter (the Carter-Torrijos treaties), signed on September 7, 1977 it gave the Panamanians control of the canal zone and promised them gradual control of the canal zone with complete control from December 31, 1999 subject to a right of military intervention by the U.S. In 1978 when his term as Chief of Government ended he did not seek its extension but retired and planned for a return of full civil authority by 1984. He remained commander of the powerful National Guard while his follower Aristides Royo was a figurehead president. When Torrijos was killed in a plane crash, he was succeeded as by Florencio Flores Aguilar who assumed command of the National Guard but he was soon replaced by Rubén Darío Paredes.