Cristóbal (Carlos Domingo Romualdo y Ricardo) Oudrid y Segura (Spanish pronunciation: [kɾis'toβal ouð'ɾið i se'ɣuɾa], 7 February 1825 – 13 March 1877) was a Spanish pianist, conductor, and composer. He is noted for his many contributions to the formation and development of the zarzuela genre in Spain during the second half of the 19th century. He was a gifted musician—but with little technical knowledge, which he bragged about to receive more credit from others with relation to his creations. This habit earned him the scathing criticism of people like Antonio Peña y Goñi who, nevertheless, praised the bright, sensual and cheerful ease with which Oudrid used to bring to life the true meaning of the Spanish song.

During a successful career of more than 25 years, Oudrid produced over a hundred works, many in association with other composers. His first musical presentation was the Andalusian zarzuela La Venta del Puerto o Juanillo El Contrabandista, premiered at Teatro del Príncipe in 1846. His second venture was La Pradera del Canal, a collaborative work with composers Luis de Cepeda Baranda and Sebastián Iradier, premiered at Teatro de la Cruz in 1847. As a founding father of Spanish musical nationalism, he was instrumental in bringing the zarzuela to a national status, in the company of other prominent artists such as Francisco Asenjo Barbieri, Joaquín Gaztambide, Rafael Hernando, José Inzenga, and baritone Francisco Salas, with whom he formed the Sociedad Artística Musical in 1851.

Oudrid was particularly prolific also as a bandmaster during the 1850s and early 1860s, having conducted the orchestra at Teatro Real, where renowned tenors such as Roberto Stagno (1840–1897) and Enrico Tamberlik (1820–1889) premiered, as well as the orchestra of Teatro de la Zarzuela. His last performance was the rehearsal of the opera Mignon by the French composer Ambroise Thomas.