The conservatory was established by a royal decree of 1807 in Milan, capital of the Napoleonic Kingdom of Italy. It opened the following year with premises in the cloisters of the Baroque church of Santa Maria della Passione. There were initially 18 boarders, including students of both sexes. Today it is the largest institute of musical education in Italy.
The Conservatory's Liceo Musicale for secondary school students opened in 1971. In 1981 it began an experimental collaboration with the Ministry of Education. The experimental phase ended in 2010 when it become "ad ordinamento".