The results of 54 cases of maxillary sinus squamous cell carcinoma treated between 1980 and 2002 were analyzed retrospectively. The T classification according to the 1997 UICC was as follows: 2 with stage T1, 29 with T3, and 23 with T4. Ten patients(18.5%) had lymph node metastases at diagnosis. All patients underwent combined therapy including radiotherapy, surgery, and regional or systemic chemotherapy. Fifteen patients received hyperfractionated twice-daily radiotherapy (1.2 Gy or 1.5 Gy/fraction), and the remaining 39 patients received a conventional once-daily regimen(1.5-2 Gy/fraction). The 5-year overall survival and 5-year disease-free survival for all patients were 56.0% and 46.7%, respectively. The N classification was the only significant prognostic factor for 5-year disease-free survival by univariate analysis (favoring N = 0, p = 0.04). There were no significant differences in other prognostic factors including gender, T classification (T1-3 vs. T4), hyperfractionated radiotherapy (yes vs. no), total dose (BED: < 69 Gy10 vs. > or = 69 Gy10), and intra-arterial chemotherapy(yes vs. no). Although radiation-induced cataract was observed in 9 patients, no other severe late complications developed.