Museo e tesoro del duomo di Monza, Religious museum in Monza, Italy.

The Museo e Tesoro del Duomo di Monza is a museum set in underground rooms beneath the cathedral's cloister, entered from Via Lambro to the left of the façade. Its layout, designed by architect I. Battistoni, was inspired by Franco Albini's Museo di San Lorenzo in Genoa. The original 1963 structure was expanded and reopened in 2007 with a two-level subterranean section designed by Cini Boeri, holding works from the 14th to the 20th century.

The museum was founded in 1963 as the Museo Serpero, in an underground space beneath the cathedral cloister designed by I. Battistoni and modelled on Franco Albini's Museo di San Lorenzo in Genoa. It was greatly expanded and reopened in 2007 with a new section designed by Cini Boeri and Roberto Cassanelli, named for Carlo Gaiani. The treasure itself began with the liturgical furnishings given by Queen Theodelinda and was later enriched by Berengar I and the Visconti.

The museum's name comes from the chapter museum founded in 1963 as the Museo Serpero, renamed after Filippo Serpero. Its core is the treasury begun with the liturgical furnishings given by Queen Theodelinda of the Lombards, later enlarged by Berengar I and the Visconti. The silver reliquary busts of 1663, made by the Milanese goldsmith Aloisio Alessi for Archpriest Vela, show how later clergy kept adding to it.

The museum is located right next to the cathedral in the center of Monza, easy to reach on foot from the main square. The interior rooms can be cool, so a light layer is worth bringing regardless of the season.

The treasury lost objects during the Napoleonic years: between 1797 and 1815 it was taken to the Cabinet des Médailles in Paris, and pieces such as the Crown of Agilulf and the Gospel of Ariberto never came back, probably stolen and melted for their gold in 1804. Two silver loaves given by Napoleon for the offertory of his coronation as King of Italy in Milan Cathedral on 26 May 1805 are now kept in the museum.