AIM: To establish a nomogram model of Ki-67-positive grade 4 diffuse gliomas that can predict the survival rate of patients and has certain guiding values that are useful in treatment. MATERIAL and METHODS: Data from 146 patients with Ki-67-positive grade 4 diffuse gliomas was retrospectively obtained and analyzed using the R software. Statistically significant indicators were identified via Cox regression analysis and used to establish the nomogram. The nomogram was corrected using the C-index, area under the curve (AUC), calibration curve, and decision curve analyses (DCA). Finally, the model was externally validated using the Chinese Glioma Genome Atlas database. RESULTS: Age, treatment, and IDH status were significant. The models had a C-index of 0.743, and the time-dependent receiver operating characteristic curve had an AUC of 0.832 at 3 months and 0.829 at 6 months, indicating good discriminatory ability. Finally, a nomogram was constructed and validated using the validation and DCA curves. CONCLUSION: Age, treatment, and IDH were independent prognostic factors in patients with Ki-67-positive grade 4 diffuse gliomas. The constructed model can accurately assess the disease-specific survival rates of these patients and help inform treatment options.