Drawing on family systems framework, this study investigated the reciprocal prospective associations between marital relationship quality, parent-adolescent closeness and conflict, and adolescent depressive symptoms among families in Taiwan. The family systems theory posits reciprocity between family subsystems. However, the direction of influences between marital relationship quality, parent-adolescent relationship quality and adolescent well-being may be more unidirectional in Chinese societies due to hierarchical family values. Data were from a longitudinal survey of 2,292 parent-youth dyads in the Taiwan Youth Project. Cross-lagged path models were used to test the bidirectional associations between marital relationship quality, parent-adolescent closeness and conflict, and adolescent depressive symptoms from ages 12 to 18. Our primary hypothesis that marital relationship quality predicts parent-adolescent relationship quality, which then predicts adolescent depressive symptoms in a unidirectional manner was partially substantiated. Moreover, marital relationship quality directly predicted fewer depressive symptoms from middle to late adolescence and indirectly from early to late adolescence via parent-adolescent relationship quality in middle adolescence. We also found that child depressive symptoms predicted less parent-adolescent closeness, and more conflicts which predicted poorer marital relationship quality, particularly in early adolescence. Extending the family systems theory, findings suggest that marital relationship quality plays a dominant role in the health and well-being of Taiwanese families, especially as adolescents mature. Results highlight the importance of testing theories in families from diverse cultures.