He was a curate in two parishes, assistant secretary of the Metropolitan Curia and professor of public ecclesiastical law at the Faculty of Jurisprudence of the Pontifical Catholic University of Ecuador. In 1964 he was appointed chancellor of the Curia and served as rector of Our Mother of Mercy College.

On 17 May 1969 he was appointed titular Bishop of Tagarata and Auxiliary of Quito, receiving episcopal ordination on 15 June.

In March 1976 he was named Apostolic Administrator of Machala and was appointed Diocesan Bishop of the same see on 30 January 1978.

He was named Coadjutor Archbishop of Quito on 28 June 1980 and succeeded Cardinal Pablo Muñoz Vega on 1 June 1985. 

He has also served two terms as President of the Ecuadorean Episcopal Conference (1987-1993).

Named by the Holy See Primate of Ecuador, November 11, 1995.

Archbishop emeritus of Quito, 21 March 2003.

Created and proclaimed Cardinal by John Paul II in the Consistory of 21 February 2001, of the Title of S. Maria in Via (Our Lady in Via).

Cardinal Antonio José González Zumárraga died on 13 October 2008.