Background: The knowledge of blood group distribution is important for clinical studies, for reliable geographical information and blood bank management.

Aims and Objectives: To determine the blood group and study frequency distribution of ABO and Rh blood groups among medical students.

Materials and Methods: Our study aimed to find out the frequency distribution of ABO and Rh blood groups among the students of Karwar medical college. For this study 299 (161 males and 138 females) medical students were included. Blood was collected by finger prick method. A drop of monoclonal anti-A, anti-B and anti – D was added to a drop of RBC suspension prepared from finger prick blood and normal saline on clean glass slides and mixed well. Results of agglutination were recorded immediately. The data was expressed as percentages.

Results: This Study shows most frequently occurring blood group was O with 41.14% followed by B, A and AB. The frequency of B was 27.09%, A was 25.75% and AB was 6.02%. The Rh-positive percentage was 94.65% and that of Rh-negative was 5.35%. In Rh-positive blood group distribution, ‘O’ had maximum frequency of 39.13%, followed by ‘B’ 26.42%, ‘A’ 23.41% & ‘AB’ 5.69 %. In Rh-negative ‘A’ blood group had maximum frequency of 2.34%, followed by ‘O’ 2.01%, ‘B’ 0.68%, ‘AB’ 0.33%.

Conclusion: It can be concluded that among ABO system, O blood group frequency is more common in both sexes than other blood groups and AB being the least. Rh-positive blood group distribution frequency is more common than Rh-negative.

Keywords: ABO Blood Group; Rh Typing; Frequency Distribution; Medical Student.