Systems theory emphasizes the multidimensional interactions among elements within a system and their dynamic changes over time， to provide a crucial theoretical framework and analytical tools for investigating the onset and evolution of mental disorders. From a complex systems perspective， this review examines the influence of multi-factor interaction networks on the development of depressive and anxiety disorders， and reviews research progress on early-warning signals based on dynamical systems theory for symptom prediction. This study specifically examines two system-oriented psychological interventions： acceptance and commitment therapy （ACT） and mindfulness-based intervention for emotional distress （MIED）. Building upon their respective psychopathological models， this review elucidates the multifactorial interaction of depressive and anxiety disorders at a transdiagnostic level， and further analyzes the mechanism through which core intervention strategies adjust the key factors to achieve clinical improvement. ［Funded by General Projects of National Natural Science Foundation of China （number， 32371138）］