The electromicroscopic scanning of the changes on the surface and morphological structures of the chronic inflammated of mucosa and polyps of paranasal cavities was performed. With the help of the transmissional electromicroscopia there were also observed some changes of the lamina epithealis of mucosa of paranasal cavities and polyps. As the result, some electromicroscopic changes of the ciliar apparatus of chronic inflammated mucosa and polyps of paranasal cavities were noticed and, as well as the changes of the quality of outer morphology of the epithealis were verified with the help of the scanning electromicroscopia. The clinical research included the 20 patient samples. So, the conclusion was the presence of the denudation and reduction of the cell rows and the goblet cell metaplasia, which reduce the barrier function of mucosa. Acta Medica Medianae 2004; 43(3): 11-16.