Shiunko, topical herbal ointment, has been used in Japan for hemorrhoid and skin wound such as scratch, incision and burn. We report two cases of radiation dermatitis with erosion, which have a good outcome after treatment with shiunko. Case 1 was 72-year-old man with radiation dermatitis of bilateral inguinal region caused by postoperative irradiation for bilateral inguinal lymph node metastases from penile cancer. Re-epithelization was observed in erosion on the 10th day after applying shiunko. It showed earlier recovery from radiation dermatitis than the cases treated with topical external medicine of azulene and/or steroid. Case 2 was 60-year-old man with the perianal radiation dermatitis with pain caused by pelvic radiotherapy for recurrence of advanced rectal cancer after chemotherapy. Shiunko gave rapid relief from anal pain and the patients felt no pain on the day subsequent to applying shiunko. Shiunko hastens analgesic effectiveness and improvement of wound caused by radiotherapy.