Duarte Lobo (c. 1565 24 September 1646; Latinized as Eduardus Lupus) was a Portuguese composer of the late Renaissance and early Baroque. He was the most famous Portuguese composer of the time. Along with Filipe de Magalhães, Manuel Cardoso, and John IV, King of Portugal, he is considered to represent the "golden age" of Portuguese polyphony.
Details of his life are sparse. He was born in Alcáçovas, and is known to have studied with Manuel Mendes at Évora. His first position was as mestre de capela of the cathedral of Évora; by 1594 he was mestre de capela at the cathedral in Lisbon for forty years. He was also a professor of music at the Colégio do Claustro da Sé in Lisbon, where he taught Manuel Machado, and late in life he was director of a seminary in the same city.
While chronologically his life overlapped with the beginning of the Baroque music era, he was a composer who used the techniques of Renaissance, Palestrinian polyphony throughout his life, as could be expected in a musically conservative area isolated from the progressive musical trends of Italy and Germany. Published by Plantin in Antwerp, he produced six books of sacred music, including masses, responsories, antiphons, Magnificats, and motets.