Provided herein are antimicrobial conjugates of two antibiotic agents, exhibiting improved activity also against resistant bacteria, compared to each of the agents separately or their mixture, and having substantially no resistance emerged thereagainst, as well as processes for preparation the same, compositions containing the same, and uses thereof in medical treatments against pathogenic microorganisms. The disclosed antimicrobial conjugates are composed of aminoglycosides and non-ribosomal active antibiotics. Some of the antimicrobial conjugates are prepared via “click” chemistry.