Three new species of grasshoppers are described herein, Pseudoscopas rubromaculatus sp. nov. and Neopedies sainthilairensis sp. nov. from Parque Natural Municipal Saint'Hilaire, and Pseudoscopas itapuaensis sp. nov. of the Parque Estadual de Itapuã, both in the municipality of Viamão, State of Rio Grande do Sul, Brazil. Morphological descriptions are provided together with illustrations emphasizing the most significant diagnostic features of external morphology and male genitalia. New species were described by the body color pattern, as well as the epiproct and epiphallus morphology. Information is given about type specimens, material examined, habitat preferences and geographic localization map.