Background: The present study aims to find an association between ABO blood groups and breast cancer in the northern part of India. Method: A total of 500 cases (116 cases benign breast disease, 164 breast cancers and 220 as healthy control) were included in the present study. Relative risk has been calculated by logistic regression in different ABO blood groups. Results: The study reveals that risk of developing cancer is higher in the blood group A (RR=3.447; CI: 2.062-5.762) and AB (RR=3.659; CI: 1.893 - 7.070) than in blood group B and the difference is statistically highly significant. There is no difference in the risk of cancer between the persons having blood group B and O. Conclusion: Thus the most vulnerable blood group regarding breast cancer was found to be A and AB in comparison to blood groups B and O. This study also suggests that among the breast cancer is more likely to grow among those who have blood groups A (RR=2.157; CI: 1.222-3.808) and AB (RR=3.052; CI: 1.303-7.149) than the patients who have blood groups B and O.