Adolescent obesity is a national public health concern with significant immediate and long-term health consequences. Certain social groups in the United States, such as immigrant adolescents, have been identified as particularly vulnerable to overweight and obesity. A pattern of results coined the "immigrant paradox" that refers to the phenomenon wherein obesity is less prevalent in first-generation immigrant youth when compared with second- and third-generation peers. Seeking to better understand this concerning trend, this study examined the mediating role of several health behaviors on the relation between generation status and body mass index (BMI). Participants were 2292 Latino immigrant adolescents and emerging adults enrolled in the National Longitudinal Study of Adolescent Health. Multiple linear regression models indicated that sedentary behaviors partially mediated the relation between generation status and BMI. The findings indicate the unique role that sedentary behaviors play in explaining weight gain among Latino immigrants.