PURPOSE: To assess the outcome in patients with olfactory neuroblastoma (ONB). METHODS AND MATERIALS: Seventy-seven patients treated for nonmetastatic ONB between 1971 and 2004 were included. According to Kadish classification, there were 11 patients with Stage A, 29 with Stage B, and 37 with Stage C. T-classification included 9 patients with T1, 26 with T2, 16 with T3, 15 with T4a, and 11 with T4b tumors. Sixty-eight patients presented with N0 (88%) disease. RESULTS: Most of the patients (n = 56, 73%) benefited from surgery (S), and total excision was possible in 44 patients (R0 in 32, R1 in 13, R2 in 11). All but five patients benefited from RT, and chemotherapy was given in 21 (27%). Median follow-up period was 72 months (range, 6-315). The 5-year overall survival (OS), disease-free survival (DFS), locoregional control, and local control were 64%, 57%, 62%, and 70%, respectively. In univariate analyses, favorable factors were Kadish A or B disease, T1-T3 tumors, no nodal involvement, curative surgery, R0/R1 resection, and RT-dose 54 Gy or higher. Multivariate analysis revealed that the best independent factors predicting the outcome were T1-T3, N0, R0/R1 resection, and total RT dose (54 Gy or higher). CONCLUSION: In this multicenter retrospective study, patients with ONB treated with R0 or R1 surgical resection followed by at least 54-Gy postoperative RT had the best outcome. Novel strategies including concomitant chemotherapy and/or higher dose RT should be prospectively investigated in this rare disease for which local failure remains a problem.