Abstract: Association of restriction fragment length polymorphism (RFLP) of the parathyroid hormone (PTH) gene with bone mineral density (BMD) was explored in unrelated postmenopausal women who live in Beijing.One hundred and eighty-five healthy,unrelated postmenopausal women were selected and whose BMDs were measured by dual-energy X-ray absorptioemetry (DEXA).The genotypes of PTH were detected with RFLP method.The frequency of each genotype was bb 7.56%、Bb 28.11% and BB 64.32% respectively.ANOVA analysis showed that the forearm BMD was associated with PTH gene.The women with BB genotype have higher BMD than Bb and bb ones.Logistic regression analysis indicated that there was a significant difference between normal and osteoporosis women with bb genotype (P＜0.001).This result indicated that B allele might have some protective effects to bone mass loss.