Studies to examine the impact of end-of-life (EOL) discussions on the utilization of life-sustaining treatments near death are limited and have inconsistent findings. This nationwide population-based cohort study determined the impact of EOL discussions on the utilization of life-sustaining treatments in the last three months of life in Taiwanese cancer patients. From 2012 to 2018, this cohort study included adult cancer patients, which were confirmed by pathohistological reports. Life-sustaining treatments during the last three months of life included cardiopulmonary resuscitation, intubation, and defibrillation. EOL discussions in cancer patients were confirmed by their medical records. Association of EOL discussions with utilization of life-sustaining treatments were assessed using multiple logistic regression. Of 381,207 patients, the mean age was 70.5 years and 19.4% of the subjects received life-sustaining treatments during the last three months of life. After adjusting for other covariates, those who underwent EOL discussions were less likely to receive life-sustaining treatments during the last three months of life compared to those who did not (Adjusted odds ratio [AOR] 0.87; 95% confidence interval [CI] 0.85-0.89). Considering the type of treatments, EOL discussions correlated with a lower likelihood of receiving cardiopulmonary resuscitation (AOR = 0.45, 95% CI 0.43-0.47), endotracheal intubation (AOR = 0.92, 95%CI 0.90-0.95), and defibrillation (AOR = 0.54, 95%CI 0.49-0.59). Since EOL discussions are associated with less aggressive care, our study supports the importance of providing these discussions to cancer patients during the EOL treatment.