The discovery of ABO blood groups by Karl Landsteiner was an important achievement in the history of blood transfusion that was followed by discovery of Rh (D) antigen. The Rh blood group system is one of the most polymorphic and immunogenic systems known in humans. In the past decade, intense investigation has yielded considerable knowledge of the molecular background of this system. Study is aimed to provide data on ABO and Rh-D distribution in Delhi- NCR region and its comparison with the related studies in India and abroad.