Body image and eating regulations are important determinants of adolescent adjustment. Self-determination theory suggested basic psychological needs (i.e., autonomy, relatedness, and competence) as explanations for body image and eating disturbances, yet longitudinal research has been lacking. This research tests the implications of need experiences longitudinally among a Chinese adolescent sample (baseline N = 2566, 54.05% female, M = 13.80, SD = 1.56) using four-wave data spanning 18 months. Results from panel models showed that parental autonomy support vs. psychological control predicted changes in basic psychological needs satisfaction vs. frustration, which subsequently predicted changes in body image inflexibility, which then predicted changes in eating dysregulation and psychological adjustment. The “bright side” (need support and satisfaction) indirectly predicted improved adolescent outcomes, while the “dark side” (need frustration) indirectly predicted worsened outcomes, although the indirect effects of parental control was non-significant. Overall, the current findings support body image concerns as a need substitute pathway leading to adolescents’ compensatory behavior and maladjustment.