Oral submucous fibrosis (OSF) is a potentially malignant disorder of oral mucosa associated with multifactorial etiology such as areca nut chewing, nutritional deficiencies, ingestion of chillies, genetic suspectibility and immunologic predisposition. This condition is well recognised for its malignant potential and is particularly associated with areca nut and tobacco chewing, which is a habit practiced predominately in Southeast Asia and India with the overall revalence rate of about 0.2% to 0.5 %. Since blood group antigens are also found in epithelial cells of oral mucosa, various studies have shown the relationship of ABO blood group with certain diseases. Based on this background the aim of the present study was to evaluate the relationship of ABO blood grouping system in patients suffering from OSF. Materials and methods: The present study was undertaken at the Department Of Oral Pathology, Microbiology And Forensic Odontology, School of Dental Sciences; KIMSDU, Karad after obtaining the permission from the ethical committee of the Institution. The study sample comprised of 50 cases of Oral sub mucous fibrosis and 50 controls and statistical analysis were assessed to evaluate the relationship of ABO blood group and OSF. Results: The result for the study revealed that people with blood group B were at higher risk of developing OSF as compared to other groups.