Helicobacter pylori infects more than half of the global population and is regarded as the causative agent of chronic gastritis, peptic ulcer disease, and gastric adenocarcinoma.H.pylori strains expressing cytotoxic CagA protein are proved to be most virulent and oncogenic.Therefore the determination ofpathogens CagA-status is regarded as an important and informative approach in H.pylori infection diagnostics and in disease risk estimation.Currently immunochemical methods ofH.pylori detection and phenotyping are considered to be the most useful techniques, being minimally invasive, accurate and cost-effective.The immunochemical detection of CagA antigen is still a challenge due to the lack of characterized and standardized reagents.The aim of the work was to produce and characterize monoclonal antibodies (MAbs) against CagA protein.