Oral cancer is one of the most common major debilitating diseases affecting the world community.It is one the most commonest form of cancer in south asia especially countries like India,pakistan,bangladesh are most affected.This occurs mainly due to habits like smoking,gutkha and paan chewing and areca nut.most of people affected were between age groups third and sixth decades,so they are also prone for the systemic diseases.this will further complicate both the treatment plan,treatment.added to this, their postoperative complications and prognosis all depends on comorbid conditions like systemic diseases.so the aim of the study is identify the prevalence and risk factors associated with oral cancer .This is an Retrospective study.In this study a total 86000 patients records were analysed and after fulfilling the inclusion and exclusion criteria,a total of 53 patients from Department of Oral Oncology , Saveetha Dental College, who were diagnosed as oral cancer were considered for this study.Subjective and objective observations are recorded that includes age, gender, habits and systemic diseases of oral cancer patients. Period of study is from June 2019 to March 2020.All the datas of the patients were reviewed by an external reviewer and were tabulated.Statistics done with Chi Square test using SPSS.The results obtained in this study indicates that habits 39% and systemic diseases 45% were associated with oral cancer.Habits and systemic diseases are strongly correlated with oral cancer, these are risk factors for prevalence of oral cancer. Within the limitations of the study there are significant risk factors like habits and systemic diseases that are associated with the causation of oral cancer which has direct implications on the severity of disease and this will also enable us to pave the way for providing better comprehensive treatment for oral cancer