Abstract: The marker of mesenchymal cells - vimentin with high and moderate expression is present in both epithelial and stromal cells with "eosinophilic" forms of polyps and only in the stroma in patients with "neutrophilic" polyps. The presence of high vimentin expression indicates a high activity of mesenchymal cells. In the prognostic plan, these changes indicate future relapses. Detection of the CD68 marker, its low and moderate expression can mean low participation of macrophages in the formation of nasal polyps of both forms. The presence of single stained cells in mesenchymal clusters indicates a low phagocytic activity. The high and moderate expression of CD45 in mesenchymal clusters located in “eosinophilic” polyps confirms our assumption that these mesenchymal clusters are a “growth zone” of formations. High and moderate expression of CD138 in mature epithelial cells in all tissue samples of both forms of polyps and the lack of expression of this marker in clusters of mesenchymal formations, as well as average expression in cells located in the stroma, may indicate the origin of the latter from active mesenchymal cells. With the "eosinophilic form" of polyps, moderate and high expression of CD34 is detected. These results confirm our assumption about the formation of a new vascular system in mesenchymal clusters. Near the epithelium and in the stroma, a well-developed vascular system is also observed. An increase in the number of vessels is a sign of recurrence, and an increase in the number of newly formed vessels is prognostically unfavorable and indicates the occurrence of relapse.