Pedicled bone flap raised from the volar aspect of lower end of the radius, pedicled by the pronator quadratus has been used for the treatment of scaphoid nonunion and Kienbock's disease. From July 1991 to Jan. 1992, authors performed this procedures for 3 cases of Kienbock's disease. Patients were 2 cases in the left hand, l case in the right hand. There was no critial trauma history. Age at operation were 25, 37 and 57 years. All patients were in Stage I in 2 cases and stage II-A in 1 case of Lichtman's radiologic classification. Preoperative grip powers were 11%, 38%, 63% and pinch powers were 20%, 41%, 61% of that of normal opposite hand. Follow up periods were 28, 31 and 33 months. At last follow up roentgenographic finding shows no progression of necrosis of lunate, new bone formation, decreased sclerosis, and joint space were preserved in all cases. The fuctional results at the last follow up were as follows. Pain during motion was markedly diminished in all patients. Grip power were 57%, 89% and 96% and pinch powers were 68%, 83% and 100% of that of normal opposite hand with use of calibrated Jamar dynamometer which showes significant increase than preoperative state. The ranges of motion of wrist were as follows. Volar flexion were 40, 45 and 80 degree. Dorsiflexion were 10, 20 and 45 degree. Ulnar deviation were 10, 20 and 30 degree. Radial deviation were 10, 25 and 30 degree. This viable bone graft with blood supply gives very satisfactory clinical results.