Obesity is often associated with coronary heart disease and metabolic disorders. In this study, the relationship between obesity and metabolic disorders and between obesity and fatty liver by ultrasonography was investigated in 307 university students (18-20 years old, men: 196, women; 111). The correlation between Body Mass Index (BMI) and the thickness of subcutaneous fat (ST) was significant between BMI and the ratio between waist and hip circumference (WHR) was more significant in male students (r = 0.838, p < 0.001) than in female students (r = 0.639, p< 0.001). The incidence of fatty liver was significantly higher in male obese students (68.6%) than in female obese students (27.3%). After adjustment for BMI, ST, WHR and sigma glucose, the mean values for serum transaminase, cholinesterase, total cholesterol, uric acid, fasting plasma insulin and sigma insulin were significantly higher in male obese students with fatty liver than in male obese students without fatty liver. The present study suggested that male obese students with fatty liver are more likely to have metabolic disorders than male obese students without fatty liver.