The aim of this study was to develop a new natural preservative system to improve the weak points of natural polyhydric alcohols together with the efficiency of natural plants as a preservative. Polyhydric alcohols (glyceryl caprylate and ethylhexylglycerin) and antimicrobial plants (S. radix, A. nilotica and C. reticulata) were tested using the disc diffusion method and minimum inhibitory concentration (MIC) method for their antimicrobial activity against the common poultry pathogens, respectively. A study of the preservative efficacy of the cosmetic formulations containing the optimized preservative system demonstrated sufficient preservative efficacy against bacteria and eukaryotic test microbes. These results suggest that the natural preservative system including polyhydric alcohol extracts containing natural plants could be incorporated in cosmetic formulations.