We investigated the expression of cytokeratins 7 (CK7) and 20 (CK20) in nasal polyps on a group of 106 patients with chronic rhinosinusitis with nasal polyposis (45 women - 42% and 61 men - 58%) who benefited from surgical procedures. Harvested biological material was analyzed in the pathology laboratory through two methods: histopathological and immunohistochemical analysis. Classical histopathological method of processing the tissues initially fixed in 10% formalin was used. The tissues were then processed by paraffin impregnation, sectioned and stained with Hematoxylin-Eosin. The immunohistochemical method was based on soluble immunoenzymatic complexes - LSAB/HRP (labeled Streptavidin Biotin) method. We used DAKO LSAB 2 System HRP (Universal DAKO Labeled Streptavidin Biotin 2 System Horseradish Peroxidase). The expressions of CK7 and CK20 in nasal polyps were analyzed.