摘要:Problem statement: Researchers have demonstrated that epistaxis is more often encountered in patients having blood group O probably due to lower expression of von Willebrand factor. We had taken up this study to find out if there is any definite relationship between the blood groups with the bleeding time and clotting time in our population. Approach: This retrospective study was conducted in the department of physiology in our institution. The available detail reports of 740 students passing through 1st year of MBBS over the years from 1999-2007 were analyzed in respect of age, sex, blood groups, bleeding time and clotting time. The blood grouping was done with the standard antisera and bleeding time and clotting time were estimated by Duke method and capillary tube method respectively. Finally bleeding time and clotting time of different blood groups were compared and statistical analysis was done. Results: In present study population O group was found in more number of cases (37.8%) than A, B and AB. Clotting time was found to be prolonged more than 6 min in maximum number of cases in B group (12.7 cases) followed by A group (8) and O group (5.8) and AB group (4.3%). Similarly bleeding time was more than 4 min in AB group in 21.8 followed by 13.9 in group B, 10.5 in group A and 9.6% in group O. Conclusion: In present study population interestingly clotting time was more in blood group AB and bleeding time in blood group B than other blood groups which was statistically significant. Further study needed to correlate the association of this finding in cases of epistaxis and hemoptysis in our population.