Objective To investigate the association between the genetic polymorphisms of osteoprotegerin gene and bone mineral density ( BMD) in elderly patients with chronic obstructive pulmonary disease ( COPD) .Methods 178 elderly COPD patients admitted in respiratory department between January 2008 and December 2009 were recruited as a COPD group. 195 elderly healthy subjects without COPD were recruited as a control group. The subjects were all chosen from the Han population in Lanzhou city, Gansu province. Pulmonary function ( FEV1 /FVC, FEV1% pred) , body mass index ( BMI) , serum calcium ( Ca) , serum phosphate ( P) , and alkaline phosphatase ( ALP) were determined in all subjects. The OPG gene polymorphisms were analyzed by polymerase chain reaction and restriction fragment length polymorphism ( PCR-RFLP) . BMD was examined by dual-energy X-ray absorptiometry. Results In the COPD group, the distribution frequency of AAGG, GATA, and GGTT in OPG HTT gene-linked polymorphic region G209A and T245G were 2.5%, 27.2% , and 72.3% , respectively, which in the control group were 2.2% , 26.9% , and 70.9%, respectively. The genotype distribution difference of two groups had no statistical significance ( P gt; 0.05) . There were also no statistical differences in BMI, serum Ca, serum P, serum ALP or BMD between different genotype subgroups in two groups ( P gt;0.05) . In the COPD group, the genotype distribution had no statistical significance between different BMD subgroups( P gt; 0.05) . Conclusion In the elderly patients with COPD from Han population at Lanzhou city, OPG HTT gene-linked polymorphic region and T245G gene polymorphism have no significant correlation with reduced lung function, reduced BMD and bone metabolism which are not likely to be susceptibility loci for osteoporosis in COPD patients.