Abstract: The morphology and histochemical characteristics of nephron in soft-shelled turtle,Trionyx sinesis,were clearly defined by light microscopy and histochemistry.The results showed that the soft-shelled turtle kidney was com-posed of several lobules,and each lobule of kidney contained the renal capsule and renal parenchyma.The latter could be divided into a medial zone(MZ) and a lateral zone(LZ).LZ was eosinophilic,and was dominated by the presence of proximal tubules and the collecting duct.MZ was weakly eosinophilic,and was characterized by the presence of renal corpuscles,distal tubules,and intermediate segments.Glomerulus was PAS-positive,both succinate dehydrogenase(SDH) showed weakly positive,however,alkaline phosphatase(ALPase),Na+,K+-ATPase and Alcian blue were nega-tive.Podocytes showed acid phosphatase(ACPase) positive.Proximal tubule brush border was eosinophilic,PAS,alka-line phosphatase,acid phosphatase and Na+,K+-ATPase-positive,and succinate dehydrogenase(SDH) was weakly posi-tive in the region.The intermediate segment,distal tubule and collecting duct were weakly eosinophilic,and showed succinate dehydrogenase-positive.The luminal of intermediate segment was a Na+,K+-ATPase weekly positive.Distal tubule cells in lateral showed a PAS-positive,the luminal epithelium showed a AB-positive.The luminal epithelium of collecting duct showed a strong PAS-positive,ACPase positive particles,Alcian Blue(AB)-positive and toluidine blue(TB)-positive particles.Bright and dark cells of Renal tubular epithelial were detected in toluidine blue stain.The re-sults of histochemical reaction and distribution indicated that cell types of renal tubules in soft-shelled turtle were more,and the proximal tubule played a major role in reabsorption original urine,distal tubule and collecting duct had a role in secretion mucus.That was different from the mammals and birds,and other reptiles.