Background and Aims: The purpose of this project was to examine body dissatisfaction and the degree of acculturation to Western media body ideals among Japanese adolescents. Furthermore, sex differences in body esteem were examined between male and female participants. Methods: Male and female participants (N=158) aged 15 to 18 years in Okinawa, Japan were surveyed about body image concerns and their degree of acculturation. Participants were recruited from churches and community sites in Okinawa. Results: An independent t-test revealed that girls internalized the thin ideal to a greater degree than boys. Pearson product-moment correlations showed significant positive correlation between acculturation and body esteem, and significant negative correlations between media influences (i.e., information and pressures subscales of the SATAQ-3) and body esteem. Conclusions: Overall, both male and female participants reported body image concerns. Japanese adolescents could benefit from an educational body image intervention that uses a cognitive dissonance approach. (Contains 2 tables.)