Ademollo studied at the Academy of Fine Arts in Brera, Milan. His tutors were Giuliano Traballesi, Giocondo Albertolli and Giuseppe Piermarini. In 1788 he arrived in Florence and decorated the Teatro della Pergola. He was made professor at the Academy of Fine Arts there also. He decorated the chapel (and other rooms) of the Pitti Palace, in the Basilica della Santissima Annunziata, and in the Pucci and Capponi palaces. He also worked for churches in Bergamo, Brescia, Lucca, Livorno, Pisa, Siena and Arezzo.