-(Richness, structure, and edaphic interactions in the restinga gradient of Parque Estadual do Acaraí, Santa Catarina State, Brazil). The present work characterized the flora and phytocommunities of a restinga gradient on the coast plain of Santa Catarina State and correlated them to edaphic attributes. The floristic survey followed the wide patrolling method and the community structure was determined through the plot method. Soil samples of each physiognomy were collected for analysis of macronutrients, organic matter, moisture, and litter thickness. Flora comprises 319 species, 244 of which occur exclusively in formations of herbaceous restinga (63), shrub restinga (32), shrub-tree restinga (46), and transition forest (103). The structural pattern of each restinga physiognomy studied was influenced by edaphic factors as organic matter, potassium, and aluminum contents, cation exchange capacity, and litter thickness. These attributes are determinant for the flora characterizing each phytocommunity.