Objectives: Adult medulloblastoma is a rare tumor, and few retrospective studies on medulloblastoma have been published to date. A standard treatment regimen has not yet been established. Accordingly, this study was designed to determine the treatment outcomes and prognostic factors for patients with adult medulloblastoma.Methods: We retrospectively reviewed all cases of adult medulloblastoma at the Beijing Tiantan Hospital between 2004 and 2007. There were 33 patients in total. Tumor removal followed by radiotherapy was performed in all patients. Five patients received maintenance chemotherapy after radiotherapy. Statistical analysis was performed using the log‐rank test, Kaplan–Meier method, and Cox regression analysis. Results: The median follow‐up period was 73 months. The 5‐year progression‐free survival(PFS) and overall survival(OS) rates were 45.5% ± 8.7% and 51.5% ± 8.7%,respectively. Recurrence or progression was observed in 21 patients, and 14 patients were still alive. Tumor location at the midline with infiltration to the floor of the fourth ventricle was associated with the worst PFS and OS(P = 0.032). Hemispheric desmoplastic/nodular medulloblastomas(DNMBs) were associated with a better outcome than midline DNMB. The average‐risk group tended to have a better 5‐year PFS rate than the high‐risk group(P = 0.065). Conclusions: Tumor location is an important prognostic marker for adulthood MB.We propose a molecular and clinical staging system should be established for adulthood MB. Further prospective clinical trials should be performed to draw a conclusion. Objectives: Adult medulloblastoma is a rare tumor, and few retrospective studies on medulloblastoma have been published. This standard was designed to determine the treatment outcomes and prognostic factors for patients with adult medulloblastoma Methods: We retrospectively reviewed all cases of adult medulloblastoma at the Beijing Tiantan Hospital between 2004 and 2007. There were 33 patients in total. Tumor removal followed by radiotherapy was performed in all patients. Five patients received maintenance chemotherapy after radiotherapy. Statistical analysis was Results using the log-rank test, Kaplan-Meier method, and Cox regression analysis. Results: The median follow-up period was 73 months. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 45.5 % ± 8.7% and 51.5% ± 8.7%, respectively. Recurrence or progression was observed in 21 patients, and 14 patients were still Tumor location at the midline with infiltration to the floor of the fourth ventricle was associated with the worst PFS and OS (P = 0.032). Heavenspheric desmoplastic / nodular medulloblastomas (DNMBs) were associated with a better outcome than midline DNMB. The average -risk group tended to have a better 5-year PFS rate than the high-risk group (P = 0.065). Conclusions: Tumor location is an important prognostic marker for adulthood MB.We propose a molecular and clinical staging system should be established for adulthood MB. Further prospective clinical trials should be performed to draw a conclusion.