Infectious diseases, especially those caused by bacterial (Gram positive and Gram negative) and fungal microorganisms, have become a serious threat to the global health system, being responsible for about a quarter of all deaths worldwide. Benzo[f]quinoline and their derivatives, some of them being structurally analogues to the steroid skeleton, are very useful compounds in various fields of chemistry, including biological and pharmacological chemistry, as well as promising candidates for use in organic light emitting diodes [1-4]. Having in view the above mentioned, our main goal was to synthesize, characterize and testing of antimicrobial properties of novel benzo[f]quinolinium salts. Using a Bruker Avance III 500 spectrometer equipped with a 5 mm PABBO detection probe, operating at 500.1 MHz for 1H and 125 MHz for 13C, the structures of newly quaternary salts were proved by NMR experiments (1H, 13C, COSY, HMQC, HMBC). The in vitro antimicrobial activity of benzo[f]quinolinium salts was determined by the method Kirby-Bauer disk diffusion, using nutrient agar medium: Mueller Hinton agar for antibacterial tests and Sabouraud agar for antifungal tests. The strain bacteria used for the antibacterial and antifungal activity are illustrated in the figure.