Objectives: To examine the relationship between puberty, sedentary behaviors, and psychosocial influences with intention for physical activity (PA) and PA. Methods: Low-income, overweight African American girls (n=72) completed 5 questionnaires that assessed PA, sedentary behaviors, and psychosocial influences. Puberty was assessed using Tanner stages. Multiple linear regression was used to examine the relationships between these measures and intention for PA. Results: Puberty was significantly associated with lower intention for PA, whereas health beliefs such as "staying in shape" and social support were significantly associated with greater intention for PA. Conclusions: Puberty, health beliefs for PA, and social support from parents and peers were significant predictors of intention for PA in low-income, overweight African American girls.