Abstract: The aim of this study is to observe the long-term toxicity and possible target organ of Shangtongxiao Capsule contents on rats, also to evaluate its safety of long-term medication.SD rats were randomly divided into three dose groups (1.0,2.0,5.0gkg-1 of Shangtongxiao Capsule contents) and a control group.The rats were consecutively drenched for 26 weeks and then recovered for 4 weeks.No abnormal signs and symptoms were observed in either group.All animals' food intake, water intake and weight gain were normal.There was no obvious abnormality of blood routine and blood diochemistry indicators after administration of 13, 26 weeks or 4 weeks' recovery.The main organs weights and relative coefficient fluctuated slightly.Also,there was no difference in the relative value of viscera/brain between the groups (p 0.05).A little amount of light brown or brown particles deposition in renal proximal tubule endothelial cytoplasm was dose-related observed in a few female rats by histopathological examination after 26 weeks' administration,which were reduced after 4 weeks recovery.There was no obvious morphological abnormality in other drug-associated visceras and organs.No delayed toxicity was observed.The results indicated that 1.0gkg-1 of Shangtongxiao Capsule content is NOEAL(no observed adverse effect level).The safety dose range is 16.67 times below the clinical dosage.