Compared to psychotropic drugs, the clinical use of Kampo medicines (Japanese herbal medicines) is unclear because of the difficulty in accumulating scientific evidence for various reasons. This study reviews Kampo medicines frequently prescribed in psychiatry and the principles of disorders of qi, blood, and fluid for their use, which are considered particularly important in this field. Kampo medicines are one of the preferred treatment modalities for patients with mental disorders in Japan, and we hope that these will become a treatment option for patients refractory to psychotropic drugs.