For the new Millennium our knowledge of persistent bacteria, disinfecting agents and safety concerns has greatly increased and to achieve predictable, complete disinfection of the root canal system with minimal side-effects, there is no doubt that more innovative basic and biological approach is needed. In this sense, the search of alternative natural preparations for the disinfection of root canals remains relevant. The aim of our research was determination the antimicrobial activity of Cotinus coggygria leaves extract water solutions against Enterococcus faecalis. Microbiological study was conducted at the Laboratory of General Microbiology of Bacteriophage Analytical Diagnostic Center. The In vitrostudies seems encouraging as 2% extract was found to be most effective against Streptococcus spp., while extract 10% solutions were observed to be most effective against Enterococcus faecalis. Pronounced antibacterial activity suggests successful application of Cotinus coggygria Scop extract solutions in Endodontic Practice. The in vivo study is in progress for recommending this novel herbal preparation as an alternative antimicrobial endodontic irrigating solution.