Anthropometry, computed tomography(CT) at the umbilical level, nutrient intake, blood pressure, serum levels of lipids and lipoproteins and response of glucose, c-peptide, insulin, and free fatty acid(FFA) during oral glucose tolerance test(OGTT) were estimated on 11 normal-weight controls and 35 overweight and obese middle-agd men. The areas of total abdominal, subcutaneous and visceral were determined by CT scanning technique. Total abdominal fat area correlated the most significantly with the levels of serum lipids, lipoproteins and insulin among several obese indices. Compared with normal-weight controls, overweight and obese men with abdominal fat lower than 29000$ extrm{mm}^2$ showed an increase in waist-hip ratio, areas of total abdominal(35%), visceral and subcutaneous fat and C-peptide response area during OGTT, though age, percent ideal body weight, body mass index, % body fat, and all biochemical indices except C-peptide response area were not different between two groups. Overweight and obese men with abdominal fat greater than 29000$ extrm{mm}^2$ showed a higher values in total abdominal fat(85%), serum levels of triglyceride, total-and LDL-cholesterol, the ratio of LDL-to HDL-cholesterol, and response areas of FFA, insulin and C-peptide during OGTT than normal-weight controls. Overweight and obese men with great abdominal fat showed an increase in alcohol ingestion and percent calorie intake per total energy expenditure, compared with normal-weight controls. Our results indicate that obesity and a certain level of total abdominal fat accumulation is required to observe abnormal levels of serum lipids, lipoproteins and insulin in Korean middle-aged men. In addition, increased alcohol and calorie intake and decreased physical activity could partly explain total abdominal fat accumulation in men.