ABSTRACT Background: There are various methods to diagnose different kinds of anaemia, but in developing countries many of the available investigation are also not feasible citing financial constraints. The present study was therefore conducted at tertiary care centre to assess RDW in different types of anemia; to investigate patients for peripheral smear picture, Iron Deficiency, Vitamin B12 Deficiency & Hemoglobinopathies wherever necessary; to determine efficacy of RDW in differentiating between Types of Anemia. Methodology: The study was conducted as cross sectional study at Department of Medicine, PCMS and RC Bhopal during the study period of 18 months. A detailed history was obtained and examination was done. The study participates were then subjected to complete blood examination using hematology auto analyzer and RDW CV and RDW SD were recorded. Results: This study included a total of 115 cases with anemia with mean age of 38.3±17.7 years. Mean RDW CV was lowest in hemolytic anemia, followed by anemia of chronic blood loss, dimorphic anemia and was highest in iron deficiency anemia (p<0.05). RDW SD was lowest in megaloblastic anemia, followed by anemia of chronic blood loss and hemolytic anemia (p<0.05). RDW CV as well as SD levels were significantly higher in severe anemia (p<0.05). Conclusions: RDW is a simple and easily available screening tool helpful in screening of anemia as well as determining its severity. Red cell distribution width is increased in iron deficiency anemia and can be used routinely to differentiate iron deficiency anemia from other types of anemias with high accuracy. It can also be used in screening severe anemia irrespective of the type of anemia. RDW can be a cost effective tool for diagnosis of iron deficiency anemia as well as determining the severity of anemia.