Jean de Castro (c. 1540 – 1611) was a Belgian composer. Although he has virtually been forgotten in the revival of renaissance music he was during his life second only to Lassus in his popularity according to the Antwerp printer-publisher Christophe Plantin.

Despite the Spanish-sounding name Castro was a local from Liège, referred to as “nostre Castro” by the poet Etienne de Walcourt. He worked in Antwerp in the 1570s and was maitre de chapelle to the Duke of Juliers, Liège, in 1580.