The collector chose dark red woodwork for the walls and the ceiling of the study to contrast with the gilded mouldings and large mirrors. Two imposing bookcases form a backdrop to the Louis XV desk on which Cerruti placed historic and modern books with precious bindings. The lectern in the middle of the desk is a work of the Palermo school in tortoiseshell and silver dating from the early 18th century. Other furniture includes a desk in the style known as a ‘bureau Mazarin’ (in memory of the chief minister of Louis XIV) inlaid with ivory, mother of pearl and brass attributed to Pietro Piffetti. In addition, there is a secretary desk probably by Giovanni Battista Galletti (formerly in the collection of Gustavo Adolfo Rol), the upper section of which was used by Cerruti for books and precious objects.

The tone of this room is set by the great works of painting that surround the mirrors: a portrait of a man (c. 1590–1600) attributed to Federico Barocci, an imposing San Benedetto tra i rovi (Temptation of St Benedict, c. 1633) by Tanzio da Varallo and a small San Gerolamo (St Jerome, second half of the 15th cenury) by Neroccio di Bartolomeo de’ Landi, developed in a contrapuntal interplay of reflections. Hanging alongside these are the Rembrandt etching Madonna and Child in the Clouds (18th century) and a small panel (1876) by Giovanni Battista Quadrone, which represents the artist pausing for a moment in the picturesque clutter of his studio to gaze at the painting of two dogs on his easel. A great lover of animals and especially dogs, Cerruti must have attached particular importance to this work, which he placed in a prominent position alongside the masterpieces of the past and next to the room giving access to the staircase. On the other side of the room, secured to the shelves of the bookcase, Pierre-Auguste Renoir’s Jeune fille aux roses (Young Woman with Roses, 1897) was the last work bought by Cerruti before his passing.