Aim The aim of the study was to assess the relationship between obesity and periodontal status as well as evaluate its association with other demographic variables like age and gender among patients in KLE Society’s Institute of Dental Sciences, Bengaluru, Karnataka, India. Materials and methods A total of 200 patients (aged between 18 and 70 years) visiting the KLE Dental College in Bengaluru were analyzed for obesity and periodontal status. The body mass index (BMI) was used as an indicator of obesity and calculated as the ratio of the subject’s body weight (in kg) to the square of the height (in meters). Periodontal status was evaluated using community periodontal index (CPI). The relationship between BMI and periodontal status was assessed using binary multiple logistic regression analysis. Results Results indicated a positive correlation between BMI and periodontitis in the study group. Logistic regression analysis revealed that risk of periodontitis increases by 38% for each 1 kg/m2 increase in BMI. The risk of periodontitis increases with increase in age and influence of gender is not found to be significant. Conclusion Obesity could be a potential risk factor for periodontitis. Estimation of the BMI could, thus, be used in periodontal risk assessment. Clinical significance Obesity, as measured by BMI, is hypothesized to be involved in immunoinflammatory alterations, including periodontitis. The study also showed that obesity can be a potential risk factor for periodontitis. The BMI measurement should be used regularly as a part of periodontal risk assessment. Moreover, periodontists should counsel obese persons regarding the possible oral complications of obesity, to diminish morbidity for these individuals. How to cite this article Gigras S, Patil SR, Veena HR, Walia KD. Association between Obesity and Periodontitis in a South Indian Population: A Cross-sectional Study. J Contemp Dent 2017;7(2):103-106.