The Portrait of Juan Martínez Montañés is an unfinished c.1635 oil on canvas portrait of the sculptor Juan Martínez Montañés by Diego Velázquez.

Some art historians have suggested that the subject is Velázquez's brother-in-law Alonso Cano, which would date it to Cano's visit to Madrid in 1658, but most agree it depicts Juan Martínez Montañés based on the resemblance to other identified portraits.

On that basis, this portrait was probably painted while its subject called on Velázquez during his visit to Madrid between June 1635 and January 1636.

Montañés was called to the Spanish royal court in Madrid in 1635 to make a clay bust of Philip IV of Spain as the modello for the Florentine sculptor Pietro Tacca to make a bronze equestrian statue of Philip which is now in the Plaza de Oriente in Madrid.

At a time when artists were often seen as craftsman, Velázquez enhances the sculptor's social status by depicting him in formal black dress with white collar and cuffs, like a nobleman.