Background: In India, buccal mucosa carcinoma is one of the commonest oral cavity tumours which are aggressive in nature. Objective: The present study aim was to evaluate survival impact of buccal mucosa carcinoma in patients treated with definitive chemo radiotherapy. Materials and Methods: All the patients with primary buccal mucosa carcinoma treated with chemo radiotherapy were included between 2013 and 2016 in regional cancer centre of Tamil Nadu. Patient’s demographic, clinical, type of chemotherapy and dose of radiotherapy and follow-up details were recorded. Results: A total of 79 patients included in the study, there were 45 (57%) male and 34 (43%) female, with a mean age of 54 years (range, 20-87 years). The chemotherapy regimen consist (Docetaxel, Cisplatin, and 5-Flurouracil) and concurrent irradiation of 66-70 Gy in 33-35 fractions over 7-8 weeks. All the patients were followed-up for 34 months (Median, 22 months). Of 79 patients, 1 (1%) identified with recurrence and 5 (6%) had diseasespecific death. Actuarial, three years estimated overall and disease-free survival was 42% and 54%, respectively. Of 79 patients, 55(70%) showed complete response and followed 23(29%) partial and 1(1%) of patients does not showed any response of treatment. After definitive chemo radiotherapy, patients had acute haematologic and non-haematologic, G3 and G4 toxicities. Conclusion: The present study demonstrated chemo radiotherapy definitive treatment response, toxicity and survival outcome of buccal mucosa carcinoma. Further, the study suggested early stage of treatment prevents distant metastasis, treatment failure and improves survival outcome.