To examine the correlation between obesity and blood pressure, smoking and drinking (define drinking: do you mean alcohol?) habit in adolescence. Methods : Data collected on 524 subjects from among Kyungwon University students who had participated in a health screening test were reviewed. With the exception of 20 subjects whose health status was deemed to be abnormal based on current illness or results of the health screening test, 504 healthy cases were analysed. We investigated the correlation between obesity as defined by BMI and blood pressure, smoking and drinking habit. Results : 1. The blood pressure of the obese group was high. 2. blood pressure was higher in smokers, and drinking did not influence blood pressure. 3. Smoking had an effect on obesity and drinking had no significant effect on obesity. Conclusions : Obesity is related to blood pressure and smoking habit. Drinking had no significant effect on obesity and blood pressure in this sample.