Objective: To research effect of different doses of Changle on the structure and function of rat liver.Methods: 180 healthy Wistar rats were divided into 5 experimental groups according following doses: 0.1,0.2,2.0,10.0 and 20.0 mg*kg-1,respectively, and the control group given physiological saline for six months. The changes of liver structure were examined by means of normal histological chemistry and transmission electron microscope(TEM). Results: The body weight of animal was linearly increased with the decrease of administered doses, gradual reduction of glycogen in hepatocytes and infiltration of inflammatory cells in the portal area were found in the group of 20.0 mg*kg-1. Changes of ultrastructure showed there were dense bodies and lysosomes containing dense granules in Kupffer cell and hepatocyte,and they were increased along with doses adding. Nuclei deformed, ALP and GPT in serum were rose in the group of 20.0 mg*kg-1. Different doses of Changle could lead to distinct biological effects. Conclusion: Long-termed administration of 20.0 mg*kg-1 Changle can lead to damage of structure and function of rat liver.