Portrait of Pier Maria Rossi di San Secondo is a painting by the Italian Mannerist artist Parmigianino, executed around 1535–1539 and housed in the Museo del Prado, Madrid, Spain.

The subject has been identified with Pier Maria III de' Rossi basing on this note, and by another from 1630 by one of his descendants about the existence of a portrait of him by Parmigianino.

The painting arrived in Spain in 1664, after King Philip IV had supported the Rossi family in a dispute with the Farnese of Parma about some territories.

The objects are also references to the count's life and personal interests: a statue of Mars, the Roman war god, an ancient bas-relief (symbol of his collector attitude), and some books, hinting to his love for literature (he was in correspondence of poet Pietro Aretino).

One of the books has the inscription "Imperio", referring to Pier Maria's commitment with emperor Charles V at the time in which the work was painted.