The son of Celedonio Romero and youngest brother of Celin and Pepe Romero made his debut as a guitarist at the age of six years and had ten years later his U.S. debut at the Hollywood Bowl. In addition to performing as a member of the Los Romeros the classical guitar virtuoso worked with the world's major symphony orchestras such as the New York Philharmonic Orchestra, the Cleveland Orchestra, the Royal Philharmonic Orchestra and the Concertgebouw Orchestra. As a student of Eugene Ormandy he made himself a name as a conductor.
1991 Romero played at New York's Lincoln Center, the world premiere of Joaquín Rodrigo's Rincones de España. The following year he joined at the invitation of Boutros Boutros -Ghali in a worldwide broadcast concert from the General Assembly Hall of the United Nations with the Spanish National Orchestra under Rafael Frühbeck de Burgos.
In the 1980s, he took with pianist George Shearing Claude Bolling's Concerto for guitar and jazz piano trio on. In the late 1980s and early 1990s, Romero turned his attention to film music. He played in 1989, the theme music in Robert Redford's The Milagro Bean Field War. For the music for Gabriele Retes film Bienvenido -Welcome, who opened the Muestra del Cine Mexico, the Film Festival of Guadalajara in 1995, he was awarded the Premio Ariel for best original film score in the same year. In 2000 he was defeated by King Juan Carlos Knight of the Order of Isabel Catolica and raised to the peerage.
Since 2000, Romero focused on the activity as a conductor. He worked with the San Diego Chamber Orchestra and in 2002 Principal Guest Conductor of the Shanghai Symphony Orchestra, the same year he also conducted the London Symphony Orchestra. He was Artist in Residence at the California Center for the Arts in Escondido and musical director of the Orquesta de Baja California in 2005.