Abstract: ［Abstract］Objective To analyze the liver function changes of type 2 diabetes mellitus rat model induced by high fat diet and streptozotocin（STZ）. Methods 65 male SD rats were randomly divided into control group （20 rats） and high-fat group（45 rats）. Rats in the two groups were fed normal diet and high-fat diet， respectively. After eight weeks feeding，eight rats were selected from high-fat group randomly and given different amount of STZ. Finally，30 mg/kg was identified as the most suitable dosage for induced the rats into type 2 diabetes mellitus. The remaining 45 high-fat group rats was injected 30mg/kg by intraperitoneal injection and then 20 rats were randomly selected from successfully established type 2 diabetes mellitus rats. Serum and liver were obtained when rats were killed after four and eight weeks. Results　Rats with type 2 diabetes mellitus showed obvious polyuria， polydipsia， polyphagia and weight loss. Their blood glucose levels were higher than 11.1 mmol/L，and the insulin sensitive index at the forth week decreased more obvious than the eighth week. Compare with the control group， liver cell disorder and vesicular fat lesions was found in the type 2 diabetic rats through the liver hematoxylin-eosin staining，the serum triglycerides（TG） increased and TG at the fourth week was obviously lower than that at the eighth week. In addition，cholesterol（TC），bile acid（TBA），Bilirubin（TBIL）， alkaline phosphatase （AKP）and alanine aminotransferase（ALT）of rats with type 2 diabetes mellitus were significantly higher than those of the control group，with statistical significances（P < 0.05），especially at the eighth week. Conclusion Rats with type 2 diabetes mellitus induced by high fat diet and STZ might have fatty liver and biliary dyskinesia.