Pascual de Gayangos y Arce (June 21, 1809 – October 4, 1897) was a Spanish scholar and orientalist.
Born in Seville, he was the son of Brigadier José de Gayangos, intendente of Zacatecas, in New Spain. After completing his primary education in Madrid, at the age of thirteen he was sent to school at Pont-le-Voy near Blois. Then, he began the study of Arabic in the École spéciale des Langues orientales of Paris under Silvestre de Sacy. After a visit to Britain, where he married, he obtained a post in the Spanish treasury, and was transferred to the foreign office as translator in 1833.
In 1837 he returned to Britain, wrote extensively in British periodicals, like The Athenaeum, and in publications of the SDUK, like The Penny Cyclopaedia for the Diffusion of Useful Knowledge and The Biographical Dictionary. In these years he completed his magnum opus as an arabist: the translation, for the Royal Asiatic Society, of the first part of Al Makkari's biography of Ibn al-Khatib. The edition was entitled the History of the Mohammedan Dynasties in Spain and appeared in two volumes in 1840 and 1843 . While in England, he entered in the Holland House circle, where made the acquaintance of George Ticknor, to whom he was very helpful. In 1843 he returned to Spain as professor of Arabic at the University of Madrid, a post he held until 1871. He entered in politics in 1881, when he was made director of public instruction. He resigned on being elected senator for the district of Huelva.
His latter years were spent in cataloguing the Spanish manuscripts in the British Museum; he had previously continued Bergenroth's catalogue of the manuscripts relating to the negotiations between England and Spain in the Simancas archives. His best-known original work is his dissertation on Spanish romances of chivalry in Rivadeneyra's Biblioteca de autores españoles. He died in London.