Gilberto Mendes started his musical education in the Conservatorio de Santos (Santos Conservatory, Brazil), his native city, where he studied piano and harmony. He was practically autodidact in composition, though he was, in contact with Claudio Santoro and Oliver Toni and attended to the Ferienkurse für Neue Musik de Darmstadt, Germany in 1962 y 1968.
In 1963 he participated in signing the Manifesto Música Nova (New Music Manifesto) in Sao Paulo, becoming one of the pioneers of the music of experimental invention, including random resources, concrete and electronic music, the use of phonemes, vocals noises, etc; new graphemes, theatric resources and mixed media.
University professor, conference speaker and collaborator of magazines and the main newspapers of Brazil, he founded in 1962 the Festival Musica Nova de Santos (New Music Festival of Santos), the oldest of its kind in Latin America.
He has been Invited Professor in several Universities of the USA. His diverse writings have been published in Encyclopedias and specialized Dictionaries, in England, Germany, France, Sweden and USA. His works have been the subject of study in Doctoral and master Theses.
Gilberto Mendes has a Doctor's degree by Universidad de Sao Paulo (University of Sao Paulo) and is a Honorary Member of Academia Brasileira de la Música (Brazilian Academy of Music). In 2002 he was elected as Corporate Member of Colegio de Compositores Latinoamericanos de Música de Arte (Collegium of Latin American Composers of Art Music).