The digestive system of giant freshwater prawn (Macrobrachium rosenbergii)has been studied with light microscopic histology and scanning electron microscopy. It was found no any tooth in cardiac stomach, but there were cuticle plates in the dorsal and ventral wall of the stomach. The midgut is rather longer, from the post part of cephalothorax to the most part of abdominal region. The free ends of epithelium cells in midgut have striated borders, and cells directly contact with the lumen of the midgut. The striated borders also appear in the tubule cells of midgut gland. The hindgut is short, has no striated border. The epithelium cells of digestive tube with or without the striated border can be used as one of important standard for distinguishing the midgut from foregut and hindgut.