Cancer is one of the leading causes of death in the United States. The Surveillance, Epidemiology, and End Results (SEER) data from the National Cancer Institute is a population based cancer registry, which geographically covers 34.6% of the US population. The SEER database was used to model surivial time for 21,524 patients with primary malignant brain tumors. The Kaplan-Meier surivial curves and the logrank test were used to compare the effect of treatment in each grade. The Cox Proportional Hazard Model was used to show the simultaneous effect of treatment, sex, and age on the risk of death for patients in each grade. Elderly patients had the lowest survival time, while adults had the highest. The risk of death for males was slightly higher than females. The results demonstrate that the survival curves of the three treatment groups only significantly differ among participants with grade 4 primary brain tumors.