Peritoneal adhesion formation is a complex biological process associated with inflammatory responses, changes in cellular activity, and remodeling of connective tissue. Macrophages—cells of the innate immune system—play a key role in these processes by regulating inflammation, phagocytosis, and tissue regeneration. The aim of this literature review is to analyze current scientific data on the functional activity of macrophages and their involvement in the pathogenesis of adhesion formation. Mechanisms of macrophage activation, features of their phenotypic differentiation, and the influence of cytokines and growth factors on the formation of connective tissue structures are considered. The literature analysis demonstrates that macrophages are an important component of the cellular microenvironment, regulating inflammation, fibrosis, and tissue repair processes.