Diffrent honey bee (Apis mellifera L.) products have shown strong antagonistic action against pathogens that cause serious health problems. Despite the recorded antimicrobial properties of certain bee products, there are few studies focused on the inhibition of the growth of multiresistant bacteria, especially those resistant to carbapenems and vancomycin, which are an alarming current problem in the world. Also, many aspects of the antimicrobial activity of bee products remain unexplained, especially in products such as chestnut honey, honeydew, royal jelly and bee venom (apitoxin). Therefore, the proposed project is aimed at determining and clarifying insufficiently researched aspects of the antimicrobial effect of these bee products on carbapenem-resistant enterobacteria and vancomycin-resistant enterococci originating from wastewater and hospitals in the Republic of Croatia. Also, the goal of this project is to carry out a detailed physico-chemical, spectroscopic and chromatographic characterization of the researched bee products in order to determine the compositional parameters responsible for their antimicrobial activity. This project will also include the development of new analytical procedures for testing the authenticity and quality of the researched bee products using sophisticated and complementary analytical tools (AFM, SEM) that will provide additional information about their constituents and morphological and mechanical properties.