The initial lineup featured Miltinho (Milton Lima dos Santos Filho, b. 1943), Magro (Antônio José Waghabi Filho, 1943-2012), Achilles (Achille Rique Reis, b. 1948) and Ruy Faria (Ruy Alexandre Faria, b. 1937). The quartet was originally known as Quarteto do CPC (Centro Popular de Cultura - Popular Culture Center). With the extinction of the CPC after the 1964 Brazilian coup d'état, the band adopted the name of MPB-4.
In 2001, MPB-4 completed a 36-year career with the same formation (registered in the Brazilian edition of the Guinness Book of Records). In 2004, Ruy Faria left the band, being replaced by Dalmo Medeiros (b. 1951), ex-member from Céu Da Boca. After Magro's death in 2012, he was replaced on band by Paulo Malaguti Pauleira as singer/composer/arranger.