Background: Anemia is a very common disease in critically ill patients. Approximately 29% of patients have lower than normal hemoglobin levels when admitted to an ICU, and about 95% develop anemia within 3 days of admission. Aim of the Work: The purpose of this study was to evaluate the effects of restrictive and liberal red blood cell transfusion strategies on mortality and morbidity in critically ill patients. And as a result, recommend the more beneficial and the less deleterious strategy for critically ill patients. Patients and Methods: This clinical interventional study was carried out at Intensive Care Unit, Benha Teaching Hospital, Egypt, during a period from July 2017 to November 2017. This study was approved by Ethical Committee of Faculty of Medicine, Ain Shams University, including the informed consents which were obtained from either the patient or the closest family member. Results: Mortality rates in ICU were 16 % and 20% in group A and B respectively, 24% and 28% within 60 days respectively. There were lower mortality rates with group A but with no statistically significant difference between groups according to mortality during ICU Stay and mortality within 60 days. Conclusion: Comparison between the effect of restrictive and liberal strategies of blood transfusion on mortality and morbidity in critically ill patients showed no significant differences. Restrictive strategy is at least as effective to liberal strategy in critically ill patients. Blood transfusion may be hazardous and cost-effective. Recommendations: Anemia is associated with adverse clinical outcomes. However, randomized clinical trials are required to establish if transfusion is beneficial or harmful in anemic patients. A restrictive transfusion strategy should be recommended within the well-studied patient populations and clinical conditions, and the clinicians must continue to use their experience and bedside clinical judgment to advocate the best management for their patients.