The diagnosis of mental disorders relies predominantly on a symptom-based descriptive diagnostic system currently, lacking reliable biomarkers and golden standards. The diagnostic method restricts the accuracy of disease diagnosis to a large extent. Traditional psychiatric diagnosis is based on medical history and mental examination. The difficulties in diagnosis include subjective judgment on disorders, lacking of multi-dimensional perspectives, and deficits in the diagnostic holism. During the psychiatric diagnosis, we should integrate syndrome clusters features, functional impairment, and illness background; We can utilize the auxiliary examinations to enhance diagnostic accuracy. Based on the efforts above, it can promote comprehensive advancements in psychiatric diagnosis, treatment, and clinical research.