Two empirical studies were conducted to test the facilitating effect of need-supportive parenting (NSP) on Taiwanese adolescents' individuating autonomy (IA) and relating autonomy (RA) as well as to investigate the mediating effect of IA and RA on the relationship between NSP and adaptation. Study 1 adopted a cross-sectional design and found that (1) NSP was positively related to adolescents' IA and RA capacity; and (2) the positive effects of NSP on intrapersonal adaptation (i.e., self-esteem and happiness) and interpersonal adaptation (i.e., empathy and reciprocal filial piety) were superiorly mediated by IA and RA, respectively. Study 2 used a longitudinal design and added negative criteria (i.e., anxiety and depression for intrapersonal maladaptation, and hostility and delinquent behavior for interpersonal maladaptation). Hierarchical linear modeling analyses indicated that (1) NSP not only positively contributed to Taiwanese adolescents' IA and RA, but also facilitated the change rate of IA and RA; (2) the changes in IA and RA within individuals over time were related to the changes in intrapersonal and interpersonal criteria, respectively; and (3) IA primarily mediated the effects of NSP on both intrapersonal adaptation and maladaptation, while RA mediated the effects of NSP on both interpersonal adaptation and maladaptation. Limitations and future directions are discussed.