In 38 patients with femorsl neck fracture trested at Cstholic Hospital from Aug. 1980 to Jun. 1985, 24 patients were followed for more thsn 2 years. Preoperative bone scanning with 99m Tc MDP was performed in those 24 patients and postoperative follow-up bone scan assesment of the femorsl vascularity was done in 9 patients of them. Following results were obtained. 1 . Tc 99m methylenediphosphonate bone scanning was effective in assesing the femoral head vascularity in the femoral neck fracture patients. 2. The femoral head activity could be changed in the postoperative scanning : there could be further injury to the blood supply during operation or femoral head revascularization after operation 3. Some information about the possibility of future avascular necrosis could be obtained by comparing preoperative and postoperative bone scan in order that early preventive measures might be applied against the late head collapse. 4. It was conculuded that internal fixation should be considered first in the treatment of fresh femoral neck fracture : the indication of head replaement surgery could not be rnade by preoperative bone scan only.