A native of southern Chad, Malloum became a high-ranking officer in the Chadian military under the country's first president, François Tombalbaye.

Following Tombalbaye's overthrow and assassination during the 1975 Chadian coup d'état, he became the country's new president, inheriting the civil war against northern rebels.

Under the terms of the Kano Accord, Malloum resigned, while a new transitional government was created using a power-sharing agreement between Habré and Goukouni.

In July 1973, he was arrested and imprisoned by President François Tombalbaye on charges of conspiring against the government, but was released after a successful coup-d'etat on 13 April 1975.

However, he was unsuccessful and resigned from the presidency on 23 March 1979,[2] after signing the Kano Peace Agreement which allowed the rebels to form a provisional government.