Objective: Examine the relationship between self-efficacy and various measures of adiposity in a sample of teens. Methods: A total of 132 teens were selected from schools participating in an existing research study titled Teen Eating and Activity Mentoring in Schools (TEAMS). Teens completed demographic questionnaires and healthy eating-specific and physical activity-specific measures of self-efficacy. Waist circumference (WC), triceps skinfold thickness (TSF), and body mass index (BMI) percentile scores were also obtained. Results: Regression analyses indicated that healthy eating-specific and physical activity-specific measures of self-efficacy predicted WC and TSF. ANOVA revealed significant differences in healthy eating-specific self-efficacy levels between students of recommended weight and overweight/obese status. Supplemental analyses showed significant negative relationships between a student's ideal BMI ratio and self-efficacy. Conclusions: Because self-efficacy may be amenable to change, these findings could inform future efforts aimed at increasing behaviors that promote healthy weight status among early adolescents. (Contains 3 tables.)