Three ships of the Brazilian Navy have been named Rio Grande do Sul:
, a launched in 1909 and decommissioned in 1948 Brazilian submarine Rio Grande do Sul (S11) (Balao class), the former American USS Sand Lance (SS-381); in Brazilian Navy service, 1963–1972; cannibalized for spare parts and scrapped by 1975 Brazilian submarine Rio Grande do Sul (S11) (Tench class), the former American USS Grampus (SS-523); in Brazilian Navy service, 1973–1993