Background: Term ‘Oral potentially malignant disorders’ is recommended by WHO in the year 2005.  It includes both oral premalignant lesions and conditions. There is a high prevalence of these lesions in India, which is attributed to culture, geographic factors, low socio–economic status and varying lifestyle factors. The genetic relation of these lesions is less studied. Blood groups play an important role in the immunogenetic system. Very few studies have been done in India to see the association between blood group and potentially malignant disorders. Hence the present study was under taken to assess the relationship between ABO Rh blood group and oral potentially malignant disorders. Materials and methods: 50 cases with oral potentially malignant disorders diagnosed based on the WHO criteria were included in the study. The patients of Jammu population were included in the study after obtaining an informed consent. Information regarding socio – demographic details was collected using proforma and blood group was assessed using blood group kit with Rapid slide test method. Result: Out of 50 cases, 27 (54%) were males and 23 (46%) females. 26(52%) cases were with leukoplakia, 18 (36%) cases were OSMF, 5 (10%) cases were oral lichen planus , and 1 (2%) case was with erythroplakia. 18(36%) of cases belonged to A+ve blood group followed by 14(28%) belonged to B+ve blood group. Conclusion: From our study we concluded that the cases with A +ve blood group were more susceptible for the development of oral potentially malignant disorders, followed by B+ve blood group.