Abstract: An aqueous, heat and cold stable, non-alcoholic or slightly-alcoholic microemulsion based antimicrobial mouthwash composition with improved antimicrobial efficacy. The composition comprises a unique water-soluble matrix composite, at least one water-immiscible or water-insoluble antimicrobial agent, and optionally, a preservative or preservative system, a weak carboxylic acid, a coloring agent and other additives. Examples of antimicrobial agents include menthol, thymol, eucalyptol and/or methyl salicylate. A process for preparing the oral care composition is also disclosed.