Background: The prevalence of Type 2 Diabetes Mellitus(T2DM) and Obesity has reached epidemic proportions. Along with these diseases, Obstructive Sleep Apnea(OSA) also has emerged as a major cause for cardiovascular comorbidities. OSA despite being an increasingly recognized entity in the western world, is still not a commonly made diagnosis in India . There is a strong association of OSA with severity of Obesity and T2DM, both as a risk factor and complication. This study aims to reinforce this association.Aim: To study the prevalence of OSA in Obese and Type 2 Diabetes Mellitus individuals.Methods: Cross sectional hospital based study done on 35 obese patients with T2DM, who were screened for OSA by clinical history, relevant physical examinations and Epworth Sleepiness Scale (ESS).Limited Polysomnography(PSG) was performed on all patients. Apnea Hypopnea Index (AHI) ≥5 was considered to have OSA.Results: Of the 35 individuals in study group, 22 (63%) had AHI ≥5. 20%, 14% & 29% of study group had Mild, Moderate and Severe OSA respectively. Age predominance was in 4^th & 5^th decade.Symptoms like Snoring, Excessive Daytime Sleepiness (EDS) were the most common symptoms, and had statistically significant association with OSA(p<0.05). Neck circumference and BMI were found to be significantly higher in OSA group compared with Non OSA group (p<0.05).Also, severity of OSA increased with increasing grades of obesity. Prevalence and severity of OSA was higher in Uncontrolled Diabetics than in Controlled diabetics. Furthermore, HbA1c values had moderate positive correlation (R=0.56) with AHI values. Conclusion: The high prevalence of OSA in obese patients with type 2 diabetes represents a serious public health problem and raises the possibility that some of the morbidity and mortality associated with obesity and type 2 diabetes may be attributable to undiagnosed OSA. Early detection and treatment of OSA in obese diabetic patients can prevent development of complications in them due to the combined effects of both diseases. Thus the need for screening obese type 2 diabetes patients for undiagnosed OSA has been reinforced by this study.