INTRODUCTION: Oral cancer is a major health problem, causing high morbidity and mortality rates. Oral Squamous Cell Carcinoma (OSCC) accounts for 90-95% of all oral malignancies. The prognosis of OSCC is often poor due to the late discovery of most lesions, after they have reached a large size. Here comes the role of biomarkers of genetic damage that can have excellent use in early diagnosis of cancer. Micronuclei are small extranuclear bodies formed by chromosome fragments or whole chromosomes that lag behind at anaphase and are not incorporated into the resulting daughter nuclei but are covered by a nuclear membrane and resemble a small nucleus. Many investigators have already called micronuclei (MN) an upcoming biomarker of tumorogenesis. More than 90% of human malignancies originate from epithelial cells. Thus the MN test in exfoliated buccal epithelial cells could be used as an objective, non-invasive tool for biomonitoring the genetic damage in high risk human populations and for screening cellular alteration in OSCC cases. OBJECTIVES: To assess the degree of genetic damage in the oral squamous cell carcinoma lesions using micronuclei as biomarkers. MATERIALS AND METHODS: A total of thirty four participants; seventeen OSCC patients and17 healthy control subjects were included. Cytological smears were taken from the lesion of the OSCC cases as well as from the buccal mucosa of the control group subjects using a cytobrush. Cytological smears were stained using Papanicolaou stain and the number of micronucleated (MNed) cells per 1000 cells was determined for each subject. RESULTS: There was a statistically significant difference between the number of MNed cells in the cytological smears of OSCC cases and those of the healthy control subjects