Purpose: The aim of this study was to examine BMI, body fat mass, percent body fat, waist-hip ratio, soft lean mass, skeletal muscle mass, and fat free mass, and to determine the association between dietary behavior and exercise and body composition among students at women's colleges, and decide on the relationships among them. Method: This study employed a cross-sectional study design and a convenient sampling method. Ultimately, a total of 404 students participated in the study, which was conducted from September 1 to December 22, 2009. Measurements administered were comprised of dietary behavior and a questionnaire on exercise. The SPSS Win 18.0 statistics program was used for analysis of final data. Results: Major findings are as follows: 9.9% of participants showed a high BMI, and more than 56% and 38% of participants showed a high percent body fat and waist-hip ratio, respectively. Dietary behavior showed a significant negative association with percent body fat (r=-0.110, p=0.027) and waist-hip ratio (r=-0.118, p=0.018). Compared with the non-regular exercise group, the regular exercise group showed a high level of soft, lean mass (t=4.15, p<0.001), skeletal muscle mass (t=3.13, p=0.002), and fat free mass (t=4.00, p<0.001). Conclusion: For maintenance of proper body composition, health promotion programs for management of dietary behavior and regular exercise for students at women's colleges should be developed.