Arnaldo Dias Baptista (Portuguese pronunciation: [aɾˈnawdu baˈtʃistɐ], born July 6, 1948) is a Brazilian rock musician and composer.

[1][2] In 1966 he formed the influential Os Mutantes band with his brother Sérgio Dias and Rita Lee, where he played bass guitar, keyboards and sang.

[3] This motivated him to try a solo career, and in the same year, he released the album Lóki?, which is considered his best work by some critics.

[3] In 2006, Os Mutantes reunited without Rita Lee, and Baptista played with his brother Sérgio and drummer Dinho Leme 33 years after originally leaving the band.

[7][8] Baptista currently lives with his wife, Lucinha Barbosa, in the city of Juiz de Fora, where he spends most of his time painting, singing and writing songs.