In order to analyse the diet of Schizodon intermedius Garavello & Britski, 1990, captures were made every season during the period of April/1990 to February/1991, using gillnets of different mesh size at Sertanópolis, a region of Paraná State. An analysis of stomach fullness degree was made upon 76 individuals (including young ones). A sample of 20 adult specimens was chose to compare the morphology of the digestive tract with the diet found. It was concluded that S. intermedius is a grazer herbivore whose principal diet consists of leaves and stalks of two monocotyledonous plants: Poaceae and/or Cyperaceae. This species shows quanlitative, but not qualitative feeding seasonal variations. It was verified that intestinal quotient of the species is X = 1.34, the variation of gill rakers number is 18-23 and of the pyloric caeca number is 15-25. These morphological characteristics found in this species are typical of herbivore fishes.