To investigate the relationship between hyperglycemia and hyperlipidemia in diabetics, eighty-six patients with non-insulin dependent diabetes mellitus (NIDDM) were followed up for 6 to 12 months. The results showed that plasma TC, TG, LDL-C levels and LDL-C/HDL-C ratio were elevated in diabetic group as compared with normal control group. Plasma TC and LDL-C levels in the diabetics with mean fasting blood glucose (mFBG) level more than 150 mg/dl were significantly higher than those in diabetics with mFBG less than 150 mg/dl, and those in normal control group as well, but plasma TC, LDL-C and TG levels showed no significant difference between diabetics with mFBG less than 150 mg/ dl and normal controls.The disturbances of lipid metabolism were obviously alleviated following the improvement of diabetic control. These results suggest that better diabetic control can be beneficial to the improvement of lipid metabolic disorders and might be helpful to the prevention of angiopathy in NIDDM patients.