series of 2,4-hexadienoic acidderivatives (S(1)-S(42)) has been synthesized and evaluated as antimicrobial agents against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger. Quantitative structure-activityrelationship (QSAR) investigation using Hansch analysis was applied to find out correlation between antimicrobial activities with physicochemical properties