BACKGROUND: Weight overestimation of Korean Americans may be associated with dietary habits and preferences for foods and tastes. METHODS: The subjects were 100 Korean Americans in New York City and LA and 100 Koreans in Seoul, who were 20-29 years old. Self-reported questionnaire consisted of age, height, weight, length of residence in US, preferences for 10 foods and 5 tastes, dietary habits and perception of self body image. Korean Americans were further divided into 3 groups according to length of residence in US. RESULTS: More Korean American women underestimated (27.3% vs. 5.8%), and less overestimated their body weights, than Korean women (31.8% vs. 53.8%, P=0.008). Korean Americans who overestimated their own body weights had significantly higher preference for salty taste and significantly lower dietary habit score regarding regular meals. CONCLUSIONS: Overestimation of self body size, rather than longer residence in US may be associated with the undesirable dietary habit and taste preference of Korean Americans, highlighting the importance of correct body image.