Traditional herbal (Kampo) medicines have been used since ancient times to treat patients with mental disorders. In the present report, we describe four patients with dysthymia successfully treated with Kampo medicines: Kamiuntanto (KUT). These four patients fulfilled the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for dysthymic disorder with easy fatigability and sleeplessness, but did not fulfill the criteria for major depressive disorder. Treatment with KUT relieved depressive status, fatigue and sleeplessness in these patients. As a result, their QOL (quality of life) was considerably improved. KUT may be useful as an additional or alternative treatment for dysthymia, especially in the field of primary health care.