[1] He attended the liceum of classics at the archdiocesan seminary of Genoa, and was ordained to the priesthood on 29 June 1966 by Cardinal Giuseppe Siri.

He received his episcopal consecration on the following 7 February from Archbishop Dionigi Tettamanzi, with Bishops Gaetano Michetti and Giacomo Barabino serving as co-consecrators.

Since 2001, he has held several posts within the Italian Episcopal Conference (CEI), including president of the administrative board of its newspaper Avvenire, and secretary for schools and universities.

On 7 March 2007, Benedict XVI selected Bagnasco to succeed Camillo Ruini as President of the Italian Episcopal Conference for a five-year term.

"[3] On 27 June 2007, Archbishop Bagnasco, along with several other prelates, attended a briefing at the Apostolic Palace on Pope Benedict's impending motu proprio allowing wider celebration of the Tridentine Mass.

[4] Two days after this meeting, on 29 June, he and forty-five others were invested with the pallium, a woolen vestment reserved for metropolitan bishops, by Benedict in St. Peter's Basilica.

[9] On 8 May 2020, Pope Francis accepted Bagnasco's resignation as Archbishop of Genoa and named Marco Tasca OFM Conv to succeed him.

[10] On 28 September 2021, shortly after returning from the International Eucharistic Congress in Budapest, he was diagnosed with COVID-19 and admitted to the infectious disease unit of Genoa's Galliera Hospital.

[16] Alfonso Pecoraro Scanio from the Italian Green Party, a vocal supporter of gay rights, said Bagnasco had made a "grave, foolish comparison which offends millions of people".

[17] Bagnasco later condemned a ruling made by the Tuscan courts in 2014 which, for the first time in Italy, recognized the marriage of a gay couple who had wed in New York.

[19] In 2019, Bagnasco cancelled three separate public prayers of reparation for a gay pride parade that was set to be held in the archdiocese but offered no explanation for his decision.