Abstract: Objective To analyze the clinical factors that contribute to lowered bone mineral density (BMD) of the lumbar vertebrae in type 2 diabetic patients. Methods Forty type 2 diabetic patients with osteoporosis and 40 age- and gender-matched healthy individuals, selected using propensity score method, were examined for BMD of the L1 to L4 vertebrae and the left femur. Age, gender, course of the disease, body mass index (BMI), fasting blood glucose, serum calcium, serum phosphate, urinary calcium, and urinary phosphate were compared between the two groups. Results BMD of the L1 to L4 vertebras was significantly lower in the diabetic group than in the healthy individuals (P<0.05). In the diabetic patients, BMD showed an obvious difference between male and female patients and was negatively correlated with the course of the disease but positively with BMI, fasting blood glucose, urinary calcium and urinary phosphate; BMD was not correlated with age, serum calcium or serum phosphate in these patients. Conclusion Osteoporosis in type 2 diabetic patients is closely related with gender, BMI, course of the disease and poorly controlled glucose level.