Squamous papilloma is a benign mass lesion of the oral mucosa.For papillomas of the tongue,surgery is recommended owing to their malignant potential;however,certain complications may be associated with surgery.A traditional Japanese (Kampo) herbal medicine,Keishibukuryogan-ka-yokuinin (KBGY),has been used to treat viral warts and various skin diseases in Japan.Therefore,the effect of KBGY on papillomas is promising.A 49-year-old Japanese man presented with a wart on his tongue that was about 3 months old.He smoked 5 cigarettes per day.He did not drink alcohol.He had no history of malignant illnesses.He was taking alprazolam for panic disorder.The patient was diagnosed with a suspected papilloma of the tongue at the Department of Otolaryngology and was advised to undergo an excision biopsy to exclude malignancy.However,he refused owing to the fear of an invasive procedure.After informed consent was obtained from the patient,KBGY was prescribed.Three months later,the wart on his tongue spontaneously prolapsed.The histopathological diagnosis was squamous papilloma.There was no indication of malignancy,and the patient discontinued Kampo treatment.He has had no recurrence in the past 3 years.KBGY is a combination of Keishibukuryogan and yokuinin (adlay seeds).Keishibukuryogan may be beneficial for skin or oral mucosal remodeling,and yokuinin may have antiviral properties.The present case report suggests the use of KBGY as an appropriate complementary therapy for squamous papilloma.