We investigated the antimicrobial activities of twelve derivatives of benzyl phenyl sulfide by using Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values against 10 microbial strains. These derivatives of benzyl phenyl sulfides were synthesized by means of the nucleophilic coupling reaction at our laboratory. MIC testing revealed that all synthetic derivatives of benzyl and 4-methoxybenzyl phenyl sulfides had no effect against the tested microbial strains. However, the compounds of 4-nitrobenzyl phenyl sulfide showed antimicrobial activity against many of the tested strains. Above all, 4-nitrobenzyl 4-chlorophenyl sulfide 11 exhibited the strongest and widest ranging inhibitory effects among the twelve synthetic compounds. We researched the antimicrobial activities of the coupling materials of sulfide. As a result, it was considered important for the expression of antimicrobial activities that the sulfide had a 4-nitrobenzyl group and 4-chlorophenyl group in the same molecule as in the case of benzyl phenyl sulfide.