Background: This study has been carried out to know the knowledge, attitude and behavior about blood donation among medical college students of Udaipur city. Human blood is an essential element of life and it cannot be substituted other than human blood. Blood is needed crucially for transfusion in multiple diseases, episodes of injuries and the only source of blood is donation. Methods: This cross- sectional study was conducted in Udaipur city of Rajasthan on medical college students, to explore their knowledge, attitude and practice on blood donation. Sample of 150 respondents was studied, during the period of October 2016- December 2016. Results: Majority of respondents was aware, and had the good knowledge on blood donation. Blood group __ampersandsignldquo;O__ampersandsignrdquo; is a universal donor is also known to majority of the subjects. The minimum age to donate blood was known to majority of the respondents and most of them were willing to donate blood with a view that the blood donation is useful and beneficial to society. Very few of the study subjects have ever donated blood and the frequency of blood donation was observed more in male donors than female. Majority of the donor__ampersandsignrsquo;s preferred to donate blood to their relatives. Conclusions: This study reveals that having good knowledge on blood donation, less number of respondents had ever donated the blood. Major steps should be initiated to overcome the obstacles with provision of adequate literature, advertisements and communication material for enhancing positive attitude of medical college students so that they start to take part willingly in voluntary blood donation. A good positive attitude may lead to higher eagerness for blood donation. .