Oral SubMucous Fibrosis (OSMF) is a chronic, pre malignant disorder of the oral cavity seen predominantly in the south east asian region. The study was conducted to determine the prevalence of OSMF among habitual tobacco chewers. The patient records were accessed and data was collected between June 2019 and March 2021. This study shows a prevalence of 31.03% of oral submucous fibrosis (OSMF) among tobacco users visiting a private dental hospital in Chennai Keywords: dental hospitals , OSMF ,prevalence , tobacco users INTRODUCTION : Oral health is the most important part of general health. The habit of chewing tobacco has developed many deleterious effects in the oral cavity often leading to oral carcinomas. Tobacco consumption is responsible for 50% of all the cancers in men and women in India (1,2) . The main contributing factor is its easy availability and cost effectiveness (3,4). Previous studies showed Paan andGutka were the most common tobacco chewing habits (5,6). India has one of the highest tobacco users in the world and is characterised by dual use of both smoking and smokeless tobacco products

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