Constance of Peñafiel, queen of Pedro I of Portugal (b. 1323)
Constanza Manuel of Villena (1315/1323 – 13 November 1345) was the daughter of Castilian nobleman and writer Don Juan Manuel (1282–1348), Duke of Peñafiel, and his second wife Constance of Aragon, daughter of James II of Aragon.

While still a child she became the first wife of future King Alfonso XI of Castile (1311–50), also a child at the time, in Valladolid. The marriage was annulled in 1327.