Oral cancer is the sixth most common type of cancer that prevails world wide. There are about 3 lakh cases reported annually. This systematic review is aimed to assess the risk of chronic mechanical trauma leading to oral squamous cell carcinoma (OSCC). Methods: Systematically evidences were collectedfrom Medline, Pubmed, Embase, Scopus and Web of science. The review includes only case- control, cross sectional, cohort studies that done in comparison with chronic mechanical trauma and OSCC. Results: Only 124 articles described chronic mucosal trauma as risk factors for oral cancers and were considered in this review. Conclusions: The review shows that chronic mucosal irritation resulting from ill-fitting dentures may be considered a risk factor for the development of oral cancer, such cancers occur commonly over the lateral border of the tongue.