Described herein is a synergistic preservative composition used for providing broad spectrum antimicrobial activity comprising: (i) about 0.1 wt. % to about 99.9 wt. % of propylene carbonate; (ii) about 0.1 wt. % to about 99.9 wt. % of one or more organic compounds selected from the group consisting of propanediol, capryl hydroxamic acid, and isopropyl methyl phenol; and (iii) about 0.1 wt. % to 99.0 wt. % of phenoxyethanol, a preservative compound, and wherein, the composition provides synergy having Synergy Index (SI) value of the total composition from about 0.05 to about 1.0. Also described is a process for preparing said synergistic preservative composition and method of using the same.