In adult life, proper bone metabolism requires efficient regulation of bone formation and resorption processes. Bone turnover markers allow for assessing the rate of bone formation and resorption processes. In menopausal period, female patients experience gradual reduction in blood estradiol levels. The deficit of estrogens leads to enhanced osteoclastogenesis and bone resorption. Alkaline phosphatase (ALP) is a membranebound enzyme that stimulates the osteoblast activity and bone mineralization. It is synthesized by osteoblasts and incorporated into the newly formed bone tissue. The produced enzyme stimulates the osteoblast activity and bone mineralization. The goal of this study is to determine the effect of hormone replacement therapy in postmenopausal women on the expression of alkaline phosphatase gene (ALPL) within the mucosal epithelium of the cheek and in peripheral blood lymphocytes. The studies show that hormone replacement therapy has no significant effect on the increase in ALPL expression within the mucosal epithelium of the cheek. Only in women having undergone ovarectomy (OV), the epithelial ALPL expression level was higher than in the remaining groups.