Osteoprotegerin gene (OPG) is an important candidate gene of osteoporosis. The objective of this study was to evaluate the association between OPG gene polymorphisms and bone mineral density (BMD). A total of 336 Chinese postmenopausal women were included in this study. OPG gene polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), created restriction site-PCR (CRS-PCR) and DNA sequencing methods. BMD was evaluated at the lumbar spine (L(2-4)), total hip and femoral neck. Two single-nucleotide polymorphisms (SNPs) (g.21775C>T and g.23367T>C) were identified and the association analysis showed significant difference of spine BMD among different g.23367T>C genotype, subjects with the genotype TT was significantly higher than those of genotype TC and CC. Such a significant difference was not observed at the neck hip BMD and total hip BMD. The g.21775C>T polymorphism was not significantly associated with spine BMD, total hip BMD and neck hip BMD in the studied subjects. These findings suggested that OPG gene polymorphisms were associated with BMD in Chinese postmenopausal women. Results from this study will be helpful in further studies to determine the role of OPG gene in osteoporosis.