Objective: Red blood cell distribution width (RDW) has been utilized as a prognostic indicator for mortality risk assessment in cardiovascular and cerebrovascular patients. Nevertheless, the prognostic significance of RDW in critically ill patients with cerebral infarction is yet to be investigated. The objective of this study is to examine the association between RDW and the risk of all-cause mortality in cerebral infarction patients admitted to the intensive care unit (ICU). Method: A retrospective cohort study was conducted using the Medical Information Mart for Intensive Care IV 2.2 (MIMIC-IV) intensive care dataset for data analysis. The main results were the all-cause mortality rates at 3 and 12 months of follow-up. Cumulative curves were plotted using the Kaplan-Meier method, and Cox proportional hazards analysis was used to examine the relationship between RDW and mortality rates in critically ill cerebral infarction patients. Results: The findings indicate that RDW serves as a significant prognostic factor for mortality risk in critically ill stroke patients, specifically at the 3 and 12-month follow-up periods. The observed correlation between increasing RDW levels and higher mortality rates among cerebral infarction patients further supports the potential utility of RDW as a predictive indicator. Conclusion: RDW emerges as an independent predictor of mortality risk during the 3 and 12-month follow-up periods for critically ill patients with cerebral infarction.