We reviewed 46 hips of the 36 patients treated with free vascularized fibular graft for avascular necrosis of femoral head with a mean follow-up of 39.9 months (ranging from 2 years to 6 years 4 months). There were thirty-four men and two women. The mean age of patients at the time of operation was 36.6 years (ranging from seventeen to fifty-seven years). The procedure was performed on both hips in ten patients. Of the 46 hips, twenty-nine were idiopathic, ten alcoholic, six steroid induced, and one traumatic. According to Ficats stage, there were eighteen in Stage 2A, fifteen in Stage 2B and thirteen in Stage 3. According to Ohzonos classification, there were four in Type 1B, forty in Type 1C and one in Type 3B. Clinical assessments according to the cause and severity of the disease were evaluated using Harris hip scoring system. Thirty-two hips(69.6%) were excellent, 9 hips(19.6%) were good, 2 hips(4.3%) were fair, and 3 hips(6.5%) were poor. Therefore clinically satisfactory results, including excellent and good, were obtained in 41 hips(89.2%). Radiographic assessments according to healing of avascular necrosis lesion and collapsing the femoral head postoperatively were performed. Thirty hips(65.2%) were excellent, 9 hips(19.6%) were good, 4 hips(8.7%) were fair, and 3 hips(6.5%) were poor. Therefore radiographic satisfactory results were obtained in 39 hips(84.8%). Clinical and radiographic assessments according to Ohzonos classification were also evaluated. Clinically satisfactory result were obtained in 6 hips(100%) of Type 1A and 3B in 33 hips(82.5%) of Type 1C. The etiological factors didn t affect the results. There were two cases of peroneal nerve palsy in which one was irreversible and one case of clawing of great toe as complications. In conclusion, free vascularized fibular graft appears to be a very effective method for Ficats stage 2A, 2B, and early stage 3 of symptomatic avascular necrosis of femoral head, in Ohzonos Type 1C which have a high incidence of collapse.