This study examined the role of media body comparison as a mediator of the relationships between psychological factors and sociocultural pressures to be thin and body dissatisfaction in both females and males. Participants were 1,386 females (mean age = 19.37 years) and 1,130 males (mean age = 19.46) from diverse backgrounds who completed a self-report questionnaire. Path analysis was used to test a cross-sectional model in which media body comparison mediated the impact of self-esteem, depressive mood, parent dieting environment, friend dieting, TV exposure, magazine message exposure, weight teasing and body mass index (BMI) on body dissatisfaction. In females, media body comparison partially or fully mediated relationships between self-esteem, depressive mood, friend dieting, magazine message exposure and BMI, and body dissatisfaction. In males, media body comparison was not a significant predictor of body dissatisfaction. This research particularly highlights the need to further examine processes that are involved in the development of body dissatisfaction in males.