Buccal mucosa scrapings from 50 individuals belonging to tribes of Koraput district in Orissa State (India), were smeared and fixed. The cells were stained adopting Feulgen technique. All the tribes are active tobacco and alcohol users. The individuals were asked about their age, sex, food habit, tobacco and alcohol consumption habit, period of consumption and daily consumption quantity. Micronuclei were scored from the smeared cells as increase in micronucleus frequency in buccal mucosa cells of tobacco and alcohol users indicates a high risk group for oral cancer. At least 1000 cells per sample were screened. The frequency of micronucleated cells is found to be higher (7.37%) in case of male individuals than female individuals (5.90%). Individuals of both sexes of age group (50-65) years show higher frequency of micronucleus. Tobacco smokers with Pika habit show higher frequency of micronucleus (7.06%) than tobacco chewers with Dungia habit (6.33%). Such increase in micronucleus frequency in buccal mucosa cells indicates that the tribes are high risk of oral cancer.