Alonso Díaz de Montalvo (1405–1499) was a Spanish jurist.
After studying law at Lleida and Salamanca, he served in high judicial and administrative offices under the Catholic Monarchs. In 1480, he was commissioned to draft the Libro de Leyes, also known as Ordeniamento de Montalvo, a unifying codification of the law of Leon and Castile that would remain in effect, in large parts, up until the 19th century.
Reichardt, Nikola (2001). "Díaz de Montalvo, Alonso". In Michael Stolleis (ed.). Juristen: ein biographisches Lexikon; von der Antike bis zum 20. Jahrhundert (in German) (2nd edition ed.). München: Beck. p. 177. ISBN 3-406-45957-9.