-(Floristic and phytosociology of three different grassland physiognomies of Southern Brazil). The purpose of this study was to evaluate the composition and structure of three different types of grassland vegetation of Southern Brazil. We aimed to discuss the floristic similarities among these areas and the influence of the Cerrado flora in their composition. Thirty plots of 1 × 1 m were placed in each area for the quantitative sampling. Additionally, species that occurred around the plots were also collected. In total, 283 species were sampled, with 163 species in CS, 87 species in CU, and 59 in CR. 36.48% (85) of the species sampled in this study also occur in the Cerrado. The cluster analysis showed that the floristic composition of the three grassland areas is significantly different due to several factors, especially the soil water system. Keywords: Campos Gerais, community structure, grassland, Paraná State, Southern Brazil Das espécies identificadas em nível específico,36,48% (85) foram citadas para áreas de Cerrado da região. As análises de agrupamento apontaram que as composições florísticas das três formações campestres são significativamente distintas entre si, isto se deve a diversos fatores, especialmente em relação ao regime hídrico do solo. Palavras-chave: Campos Gerais do Paraná, campos sulinos, estrutura de comunidade, vegetação campestre RESUMO -(Florística e fitossociologia em três diferentes fitofisionomias campestres no Sul do Brasil