Tonsillectomy is an operation generally carried out in otolaryngology. Postoperatively, the pain is very strong and it is often difficult to eat for several days. This time, we experienced a case after tonsillectomy in which rikkosan was effective for pain management. The patient was a 23-year-old woman. With a diagnosis of habitual tonsillitis, we performed her tonsillectomy. Postoperative pain was strong, however, it was difficult to use both non-steroidal anti-inflammatory drug and acetaminophen due to the history of drug eruption. Pain was alleviated immediately after taking rikkosan Subsequently we managed pain by using rikkosan as needed. Following a good postoperative course, she was discharged 6 days after surgery.