We report three cases of patients with mental illness suffering from symptoms associated with menstruation, which were improved with Kampo treatment. Case1: A 39-year-old female had been in a depressive state after delivery and diagnosed with persistent mood disorder in the Neuropsychiatry Department of Fukushima Medical University (FMU). During treatment for the disorder, she developed premenstrual dysphoric disorder (PMDD) and was immediately hospitalized. After she was introduced to the Obstetrics/Gynecology Department, we treated her with Kampo medicine such as tokakujokito considering the meaning of the pattern (sho), and then she recovered from PMDD. Case2: A 29-year-old female with schizophrenic disorder treated in the Neuropsychiatry Department of FMU was referred to the Obstetrics/Gynecology Department due to PMDD. We administered Kampo medicine such as kamishoyosan, nyosinsan and saikozai when yang pattern was observed, and ninjinto and daikenchuto in yin sho. Then, her condition then gradually improved. Case3: A 37-year-old female diagnosed with borderline personality disorder and attention deficit hyperactivity disorder was hospitalized in the Neuropsychiatry Department of FMU. She was introduced to the Obstetrics/Gynecology department due to dysmenorrhea and PMS. After she was treated with keishibukuryogan and hangekobokuto, her symptoms improved. In conclusion, Kampo treatment appears to be effective for symptoms associated with menstruation in women with mental illness.