He was the son of José María Gil-Robles y Quiñones, leader of the CEDA and a prominent figure in the period leading up to the Spanish Civil War, and Carmen Gil-Delgado Armada.

[3][2] In 1959 he became a lawyer in the Francoist Courts, a position he held during the Spanish transition to democracy and the democratic Congress of the Deputies.

[2] was also editor of the "Boletín de Legislación extranjera" (Foreign Legislation Bulletin) and between 1959 and 1964 he was a professor of Political Law at the Complutense University of Madrid.

[2] In 1989, and after the re-foundation of People's Party, Marcelino Oreja asked Gil-Robles to accompany him in the candidacy for the 1989 European Parliament election.

[2] In January of that year he was elected President of the European Parliament after obtaining a large majority of 338 votes,[4] office he held until 1999.