Gerosa was a comune (municipality) in the Province of Bergamo in the Italian region of Lombardy, located about 50 km northeast of Milan and about 20 km northwest of Bergamo. As of 31 December 2004, it had a population of 381 and an area of 10.1 km2. Gerosa bordered the following municipalities: Blello, Brembilla, Corna Imagna, Fuipiano Valle Imagna, San Giovanni Bianco, San Pellegrino Terme, Taleggio. In 2014 the municipality of Gerosa was merged with Brembilla and the new municipality is named Val Brembilla.

Demographic evolution