We aimed to evaluate the influence of exogenetic insulin on bone mineral density (BMD) in Type 2 Diabetes Mellitus (T2DM). Group A included 120 cases of middle-aged male patients with type 2 diabetes mellitus were administrated exogenetic insulin (40 cases in Group A1: for less than 1 year; 40 cases in Group A2:for 1 to 3 years; 40cases in Group A3: for 3 to 5 years), and another 120 cases (Group B) of middle-aged male patients with type 2 diabetes mellitus were administrated insulin secretagogues. The measurements of BMD of lumbar vertebra (L2-4), collum femoris and total body were conducted with dual-energy X-raya bsorptiometry, followed by the determination of glycosylated hemoglobin, plasma insulin concentration (fasting and postprandial), and fasting C-peptide. Our results revealed that there was no statistical difference of BMD (P&>0.05) between patients in Group A1 or A3andpatients in Group B (B1, B2 or B3), while the BMD in Group A2 increased significantly (P&<0.05). And the fracture risk in Group A3 increased significantly (P&<0.05) compared with Group B (B1, B2 or B3), Taken together, exogenetic insulin significantly increased BMD and fracture risk of middle-aged male patients with type 2 diabetes mellitus.