Objective: To determine the prevalence of hypogonadism in Asian Indian patients with type 2 diabetes mellitus (T2DM) and to correlate it with components of the metabolic syndrome and microvascular complications of T2DM. Methods: One hundred consecutive male patients with T2DM between 25 and 50 years of age and 50 age-matched healthy adults without diabetes underwent assessment. Calculated free testosterone was derived by using serum total testosterone and sex hormone-binding globulin. Those patients with 2 calculated free testosterone values less than 64.8 pg/mL were diagnosed as having hypogonadism. Results: Of the 100 patients with T2DM, 15 (15%) were found to have hypogonadism-7 of 29 (24%) between 31 and 40 years of age and 8 of 67 (12%) between 41 and 50 years old. None of the 4 patients between 25 and 30 years old had hypogonadism. Eleven patients (73%) had hypogonadotropic hypogonadism, and 4 (27%) had hypergonadism. Among the control subjects, the prevalence of hypogonadism was 10%. In comparison with Western data, we found a higher prevalence of hypogonadism in patients with T2DM, especially in those in the 4th decade of life. The prevalence of hypogonadism was higher in obese patients, although it did not reach statistical significance. No statistically significant correlation was observed between hypogonadism and age, duration of diabetes. glycemic control, androgen deficiency symptoms, or microvascular complications. Conclusion: The prevalence of hypogonadism was higher in the patients with diabetes than in the control subjects, although the difference did not reach statistical significance. There was no correlation of hypogonadism with components of the metabolic syndrome or microvascular complications of diabetes mellitus. (Endocr Pract. 2009;15:513-520)