Monte Isola (also known by the name of the main island Montisola; Brescian: Muntìsola) is a town and comune in the province of Brescia, in Lombardy. It is one of I Borghi più belli d'Italia ("The most beautiful villages of Italy").

It is located on the islands Montisola (the major island, from which it takes the name), Loreto and San Paolo in Lake Iseo and, as of 2015, its population is 1,770. Monte Isola's population is approximately spread over eleven villages and hamlets. There are several churches built between the 15th and the 17th century with frescoes, statues, altars in vernacular art.

The municipality covers a total area of 12.8 square kilometres (4.9 sq mi); the main island, Monte Isola, with an area of 4.5 square kilometres (1.7 sq mi) ranks as the largest lake island not only in Italy, but also in South and Central Europe, but is dwarfed by the large lake islands in Northern Europe.