In the Brazilian state of Rio Grande do Sul, the term cerrito was traditionally used to designate archaeological phenomena that emerge in the form of mounds in different landscapes. Except for recent research developed in the southwestern region of the Patos Lagoon, few advances have occurred since the 1980s in the study of cerritos in Brazil. This article presents an analysis of the lithic industries of sites with mounds in the southwestern region of the Patos Lagoon and in the central region in the current territory of Rio Grande do Sul. The results, along with other data from the sites, suggest that coastal sites were occupied by sedentary fisher-hunter-gatherers, who also possibly domesticated certain plants. Lithic material was scarce there and was mainly produced from pebbles and quartz cobbles using the anvil technique. In contrast, central region formations presented mounds on outcrops, using land, pebbles, and boulders; the area was occupied by a hunter-gatherer group that had projectile points and other instruments carved mainly by façonnage and débitage.