Brazil never trailed and was never seriously challenged.
Barbosa, who plays for the Toronto Raptors, and Vieira hit back-to-back 3-pointers to give Brazil (2-2) a 25-9 lead at the end of the first quarter.
The Brazilians were up 42-21 at halftime and continued to extend its lead in the second half. China (O-4) could not slow down Brazil's attack. Guilherme Giovannoni drained a 3-pointer to give Brazil a 70-38 lead at the end of the third quarter.
Zhu Fangyu led China with 13.