Renato Corti was born in Galbiate in the province of Lecco, part of the Archdiocese of Milan on 1 March 1936.

He studied at the seminary in Milan and was ordained on 28 July 1959 by Cardinal Giovanni Battista Montini (later Pope Paul VI).

He received episcopal ordination on 6 June 1981 from Archbishop Carlo Maria Martini, with Bishops Libero Tresoldi and Bernardo Citterio as co-consecrators.

The same pope named him Bishop of Novara on 19 December 1990 to succeed Aldo Del Monte, and he was installed on 3 March 1991.

[1] In November 2007, four months after Pope Benedict XVI issued new rules about use of the 1962 Roman Missal (see Summorum Pontificum), three priests in the Novara diocese refused to celebrate Sunday Mass unless allowed to celebrate the Tridentine Mass exclusively.