Abstract: Using 12 kinds of antisera raised against mammalian from insects,fishes and mammalian,the APUD(amine pricursor uptake and decarboxylation)cells in the body of the first-fifth zoeal stages(Z1-Z5), a megalopal stage(M),a larva stage(L)of Chinese mitten-handed crab(Eriocheir sinensis)and in the digestive system of it's adult stage were identified and localized by using immunocytochemical technique of the strept avidin biotin-peroxidase complex method. The results showed that the immunoreactive positive cells in the body of the Z1-Z5,M and L of E. Sinensis were not found;9 kinds of antisera immunoreaction of nerve fiber protein,insulin,vasoactive intestinal polypeptide,calcitonin,5-hydroxytriptamine,calcitonin gene related peptide,growth hormone,calmodulin and molting hormone were found in the different parts of digestive system of E. Sinensis adult except hindgut. However 3 antisera of immunoreactive positive reaction of glucagon,substance P and neuron specific enuolase were not found in the digestive system of E. Sinensis adult. In present paper,the distribution of the above 9 kinds of immunoreactive positive reaction in the digestire system and their characteristics were described emphatically.