Objectives : This study is to examine associations between diet and eating behavior with body mass index(BMI) in Korean office ladies. Methods: From OCT 2004 to OCT 2005, we collected obese office ladies who visited to the oriental obesity clinic and control group who were matched by age, occupation, working hours. Weight and height were self-reported. Subjects were divided to obese and non obese group by body mass index(BMI). Diet, eating behavior were determined from 21-item self-administered questionnaire. Independent paired t test was used for analyzing associations between diet, eating behavior and body mass index(BMI) Results: There were 141 participants in obese group and 50 participants in control group. Eating fast, skipping breakfast, night eating habit(p<.001), eating fatty food, drinking alcohol were highly positively associated with body mass index(BMI) values. There was no conclusive evidence that diet except fatty food were related to obesity. Conclusions: Eating behaviors are strongly related in obesity but associations between diet and obesity are not clear.