Objective To investigate the expression level of RIZ1 and Ki-67 in astrocytomas of different grades and its association with patient prognosis. Methods The expression of RIZ1 and Ki-67 in glioma tissues were evaluated immunohistochemically in 51 patients with gliomas. The correlation of RIZ1 immunoreactivity with clinicopathological featurees and the prognostic value of RIZ1 in patients were also analyzed. Results Immunohistochemistry showed a decrease in RIZ1 labeling index in high grade gliomas versus low grade gliomas (7.55±4.39% vs 48.83±4.34%,P<0.0001). There was a negative correlation between RIZ1 and Ki-67 immunoreactivity (Spearman r =－0.8130, P<0.0001). Clinicopathological evaluation suggested that RIZ1 expression was negatively associated with tumor grade and patient age (P<0.05). Kaplan–Meier survival analysis revealed a significantly positive correlation between levels of RIZ1 immunoreactivity and PFS (progress free survival, PFS). Univariate survival analysis revealed significant relationships between expression of RIZ1, expression of Ki-67, and prognosis. Multivariate analysis using the Cox proportional hazards model for all variables included in univariate analysis revealed that high RIZ1 expression was independent prognostic factors for patients with gliomas. These results suggest that RIZ1 expression may be a key prognostic index for glioma patient survival. Conclusion: We conclude that high RIZ1 labeling index indicates lower grade of gliomas, and associated with increased patients’ PFS and overall survival (OS). RIZ1 may be a potential tumor suppressor in the development of gliomas.