The freshwater crab Sinopotamon henanense is a species commonly found in freshwaters of China.However,the relevant studies on digestive system of S.henanense have not been reported yet.In the present study,morphological and histological observation of digestive system of the freshwater crab S.henanense was performed based on paraffin section technique,H.E.staining method and light microscope technique.The results showed that the digestive system comprises digestive tract and digestive glands.The digestive tract is composed of esophagus,stomach,midgut and hindgut.The digestive gland is hepatopancreas.The stomach of the crab is divided into cardiac stomach and pyloric stomach.There is a gastric mill with calcified teeth,ridges,spines and setae in the cardiac stomach,which is used to grind food.There are several special structures such as combs in the pyloric stomach,which are for food filtration.The results of light microscopy showed that the wall of esophagus,midgut and hindgut is surrounded by mucosal,muscular and connective tissue layers.The ridges in the surface of epithelium mucosa of each segment of the digestive tract wall take the shape of multigrade wrinkles.The muscular layers consist of longitudinal muscle,striated muscle and radiant muscle.Only in the midgut there are typical microvilli.The epithelium of the digestive tract is covered by cuticle except the midgut.There are more developed cilia on the surface of epithelial mucosa of esophagus and hindgut.The hepatopancreas is composed of several ramose hepatic ducts.Each hepatic duct consists of four types of cells:resorptive cells(R cell),blister-like cells(B cell),fibrillar cells(F cell)and embryonic cells(E cell).The relationship between the tissues and functions of the digestive system were discussed.These results will provide the basic data for the study of digestion physiology of freshwater crabs.