Just beyond the Museum's entrance, on the right, stands the Monument to the memory of Luigi del Moro (Livorno 1845 – Florence 1897), the architect who, as a disciple of De Fabris, completed the 19th-century façade of the Cathedral and later designed the first nucleus of rooms of the Opera del Duomo Museum.

Designed by architect Giuseppe Castellucci in 1902, the monument consists of a grey sandstone and pink marble frame, a plaque with a commemorative inscription, and a bronze portrait bust sculpted by Ida Gelli. The bust was donated by her husband, the painter Edoardo Gelli.

Set against a circular background of pink marble and surrounded by a wreath of grey sandstone, the architect del Moro is depicted wearing a jacket, shirt, and bow tie, with short hair and a prominent mustache, his expression serious and solemn. The monument remains in its original location, in the courtyard of the Museo dell’Opera.