Bergamo Cathedral (Italian: Duomo di Bergamo, Cattedrale di Sant'Alessandro) is a Roman Catholic cathedral in Bergamo, Italy, dedicated to Saint Alexander of Bergamo, patron saint of the city. It is the seat of the Bishop of Bergamo.
From no later than the 9th century there were two cathedrals in Bergamo: one was the basilica of Saint Alexander, which stood on the site believed to be that of his martyrdom, and the other was dedicated to Saint Vincent, construction of which apparently began in the Lombard era, on the site of the present cathedral. Bishop Giovanni Barozzi commissioned the rebuilding of the cathedral of St. Vincent in the mid-15th century, for the plans of which Filarete claimed credit.
In 1561 the Venetians demolished the cathedral of St. Alexander for reasons of military expediency, leaving St. Vincent's as the sole survivor. At the beginning of the 17th century, Bishop Giovanni Emo unified the canons of the two old cathedrals. Finally, Bishop Gregorio Barbarigo succeeded in obtaining from Pope Innocent XI the bull Exponi Nobis of 18 August 1697, which established for the diocese a single chapter and a single cathedral, changing the dedication of the surviving cathedral to Saint Alexander from Saint Vincent.
In 1689, the structure was refurbished to designs by Carlo Fontana. Another major renovation was undertaken in the 19th century, culminating in the completion of the Neo-classical west front in 1889.