Cardinal Lozano Barragan was born in Toluca (Mexico) on 26 January 1933. He studied for the priesthood in Zamora and at the Pontifical Gregorian University in Rome. He has a doctorate in theology.
He was ordained in Rome on 30 October 1955. He has held a number of theological responsibilities in his diocese of Zamora and for the Episcopal Conferences of Latin America (CELAM).
He was appointed auxiliary Bishop of Mexico City on 5 June 1979. He was consecrated by Cardinal Corripio Ahumada, Archbishop of Mexico City, on 15 August 1979.
He was later appointed Bishop of Zacatecas on 28 October 1984.
He was appointed President of the Pontifical Council for the Pastoral Care of Health Care Workers on 31 October 1996.
Pope John Paul II elevated him to the College of Cardinals on 21 October 2003.