Background & objectives: Epidemiological data of oral mucosal abnormalities (OMAs) are required to develop practical oral care policies. However, limited data are available for rural / urban areas in Tamilnadu. We aimed to estimate the Prevalence of OMAs and to identify their association between age and sex. Materials and methods: This retrospective study was conducted in the Department of Dental Surgery, Chengalpattu Government Medical College & Hospital. Information on diagnosed oral lesion, age and gender were evaluated. Results: The prevalence of Oral Mucosal lesions were 27.9%. The most prevalent oral mucosal abnormalities were frictional keratosis, followed by Fissured tongue, Leukoedema, Smoker’s palate, Aphthous ulcers, traumatic ulcers etc. Conclusion: The high prevalence of OMAs necessitates adequate awareness and management of these lesions in the general population. Dental clinicians should be knowledgeable and familiar with the etiopathogenesis, clinical presentation, diagnosis, and management of these lesions. We conclude that there was a highly significant association between these oral lesions, age and gender.