Forearm flap has been widly used in reconstruction of the head and neck region because of its outstanding good qualities: thin skin, a small quantity of fat tissue, long vascular stem, wide lumen of arteria radialis, and the choice of more veins for anastomosis. After flap elevation, donor site is mostly coverd by skin graft. But donor site complication has been frequently reported. A rate of tendon exposure, one of the most common complications, ranges from 6.7% to 53%. Improper treatment of tendon exposure may result in severe scarring and limitation of wrist motion. We experienced a tendon exposure in a patient who diagnosed oral cancer and underwent wide excision of lesion and reconstruction by use of radial forearm flap. Our experience in the treatment of the tendon exposure is presented.