OBJECTIVE No study has been conducted to evaluate the association between avascular necrosis of the femoral head and diabetes. This study's aim was to assess this issue in Taiwan. RESEARCH DESIGN AND METHODS A population-based cohort study was performed to analyze the database of Taiwan's National Health Insurance Program. There were 27,869 subjects aged 20-84 years with newly diagnosed diabetes from 2000 to 2012 as the group with diabetes. The group without diabetes included 111,476 sex-and age-matched subjects without diabetes. The incidence of avascular necrosis of the femoral head at the end of 2013 was measured. A multivariable Cox proportional hazards regression model was used to measure the hazard ratio (HR) and 95% CI for avascular necrosis of the femoral head associated with diabetes. RESULTS The overall incidence of avascular necrosis of the femoral head was 1.37-fold higher in the group with diabetes than in the group without diabetes (6.53 vs. 4.76 per 1,000 person-years [95% CI 1.31-1.43]). After adjusting for confounders, the HR of avascular necrosis of the femoral head was 1.16 (95% CI 1.11-1.21) for the subjects with diabetes compared with the subjects without diabetes. CONCLUSIONS Patients with diabetes have a 1.16-fold increased risk for developing avascular necrosis of the femoral head.