Objective This study aimed to explore the association between blood lipid indices and bone mineral density (BMD).Methods A total of 2,396 individuals (1 198 males and 1 198 females,average age 55.24±12.12 years) who underwent physical examination between April 2015 and April 2016 at the medical examination center of the Inner Mongolia Autonomous Region People's Hospital were recruited.The blood lipid indices,including high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C),total cholesterol (TC),and triglycerides,were collected,and BMD at the total hip and its sub-regions was measured.The association between lipid indices and BMD was analyzed using SPSS 16.0 software,with adjustment for the covariates of age,sex,height,and weight.The association between blood lipid indices and BMD was then tested by linear regression analysis.Results Regression analysis demonstrated that in the combined sample with both sexes,HDL-C was negatively associated with total and sub-region BMD (regression coefficients,-0.11 to-0.06;all P＜0.01).LDL-C was negatively associated with femur neck BMD (regression coefficient,-0.01;P=0.01) and Ward's triangle BMD (regression coefficient,-0.01;P＜0.01).TC was negatively associated with trochanter BMD,femoral neck BMD,and Ward's triangle BMD (beta coefficients,-0.02 to-0.01;P＜0.05).In the female group,TC was positively associated with trochanter BMD (regression coefficient,0.06;P＜0.01).In the male group,both LDL-C and TC were negatively associated with femoral neck BMD (regression coefficients,-0.05 and-0.04,respectively;P＜0.05).Conclusion While blood lipid indices are associated with sub-region and total hip BMD,the association pattern and magnitude vary according to body region and sex.