Giant cell tumor of bone is relatively common neoplasm usually involving epiphysis of long bone. And rarely it involves the diaphysis or metaphysis without epiphyseal extension. We report on an 18-year-old girl with giant cell tumor of ulnar diaphysis. She was treated with wide excision and reconstuction with nonvascularized autogenous fibular graft. We harvested fibular fragment preserving fibular continuity to reduce donor site morbidity. Surgical outcome and functional result was excellent.