The main cause of mortality in type 2 diabetes mellitus is a cardiovascular disease. Among the many risk factors of atherosclerosis in diabetic patients, LDL(low density lipoprotein) cholesterol is now being regarded as one of the most important modifiable one. Recent researches have revealed that the plasma LDL could be sub-divided according to the size of the particles into large buoyant LDL and small dense LDL. Small dense LDL is very atherogenic. Increased plasma triglyceride and the presence of insulin resistance are proved to be positively correlated well with the amount of small dense LDL in diabetic patients.