Although radiotherapy improves cure rates in head and neck cancer patients, osteoradionecrosis still remains a devastating complication. Once it occurs surgical treatment is necessary in the vast majority of the cases. Twelve patients were operated on by using microvascular free tissue transfer for treatment of osteoradionecrosis of the maxilla between April 1996 and August 2002. There were 10 male and 2 female patients with an average age of 60.2 years. The radiotherapy dose was obtained in 9 patients and the mean dose was 6674 cGy. Radical sequestrectomy, soft tissue debridement, pathologic proof of no tumor recurrence and microvascular free tissue transfer were performed in all patients. Free flaps used in this series were as follows: 7 anterolateral thigh, 2 radial forearm, 2 rectus femoris musculocutaneous, and 1 supracondylar. All flaps survived completely. In the follow-up period (mean: 25 months) ectropion, plate exposure, mild infection occurred in three consecutive cases and were treated successfully. Radical debridement is the primary goal for successful treatment of osteoradionecrosis of the maxilla. The defect created after debridement can be ideally reconstructed by microvascular free tissue transfer and anterolateral thigh flap is the most versatile soft tissue flap for this purpose.