Background: A woman’s entry into the menopause period is associated with a number of changes in the body, including those related to the immune system. Immune aging is a consequence of age-related changes in the function of immune cells and the composition of their subpopulations. Menopausal hormone therapy (MHT) is thought to partially neutralize the negative effects of aging on the immune system. Objective: We aimed to evaluate the effect of oral and transdermal MHT on cellular immunity parameters and cytokine profile in menopausal women. Methods: Fifty peri- and early postmenopausal women were included. Immune parameters were assessed by flow cytometry and multiplex analysis. Results: We showed that different routes of MHT administration led to significant changes in monocyte phenotype and a decrease in monocyte chemoattractant protein-1 (MCP-1) level in menopausal patients. In addition, oral MHT resulted in a significant increase in NK and B cells. A significant increase in the number of T-helper cells was observed with transdermal MHT. In addition, oral MHT resulted in a significant decrease in IL-1β level. Conclusions: We have demonstrated for the first time that oral therapy, in contrast to transdermal therapy, has a more pronounced effect on specific immune subpopulations of blood cells in menopausal women. This effect is likely to be responsible for its anti-aging properties in the context of immune aging as well as its protective effects in infectious diseases. Perhaps testing blood immune parameters or assessing immune status before prescribing MHT could become a routine step in clinical practice before choosing a patient management strategy.