Background and Objectives: Maxillectomy is the mainstay of treatment for malignant tumors of the maxillary sinus(MS). Nevertheless, few have been reported on the surgical outcomes of maxillectomy for malignant tumors of MS in Korean literature. Based on our clinical experience, the authors aimed to present the treatment outcomes of maxillectomy for squamous cell carcinomas(SCC) of MS. Subjects and Methods: We reviewed the medical records of 26 cases of maxillectomies with see of MS, who were treated from 1995 to 2004 at Samsung Medical Center. Most patients(73.1%) were locally advanced stage(T3 or T4a) at initial presentation. Total maxillectomy was performed in 18 cases, which is the most frequent procedure(69.2%). We analyzed the treatment outcomes of see of MS and several variables includeing tumor stage and resection margin to identify predictors for treatment failure after maxillectomy. Follow-up duration ranged from 7 to 89 months with a mean of 33 months. Results: Treatment failure occurred in 7 cases(26.9%), among which 3 were salvaged. Three of 26 maxillectomies(11.5%) showed the positive or close(less than 5mm) resection margin in their posterior resection sites; however it did not coincide with the site of recurrence after radiation therapy. Among patients who had been followed up for more than 6 months, disease-free 3 year survival rate was 100.0% in T1 and T2, 76.2% in T3, 60% in T4a, and 69.6% in total. Conclusion: Even though most of see of MS were detected at locally advanced stage, maxillectomy with or without postoperative radiation therapy for resectable MS see(T1-T4a) provided the acceptable treatment outcome(70%, 3Y disease-free survival rate).