Oscar Castro-Neves (May 15, 1940 – September 27, 2013), was a Brazilian guitarist, arranger, and composer who is considered a founding figure in bossa nova.

He was born in Rio de Janeiro as one of triplets and formed a band with his brothers in his youth. At 16 he had a national hit with Chora Tua Tristeza. In 1962 he was in a bossa nova concert at Carnegie Hall, and later he toured with Stan Getz and Sérgio Mendes. He went on to work with musicians from different genres, including Billy Eckstine, Yo Yo Ma, Michael Jackson, Barbra Streisand, Stevie Wonder, João Gilberto, Eliane Elias, Lee Ritenour, Airto Moreira, Toots Thielemans, John Klemmer, Carol Welsman, Stephen Bishop, and Diane Schuur.