2-[4-(substituted benzylidenamino)-5-(substituted phenoxymethyl)-4H-1,2,4-triazol-3-yl thio] acetic acid (3a-j) derivatives have been synthesized by the reaction between 4-(substituted benzylidenamino)-5-(substituted phenoxymethyl)-2H-1,2,4-triazol-3(4H)-thiones (2a-j) and chloroacetic acid containing catalytic amount of pyridine. All these compounds were screened for antimicrobial activity. The compounds 3h and 3j exhibited good antifungal activity against A. niger, C. Neoformans, and A. fumigatus at MIC of 0.25 μg/ml compared to standard drug fluconazole at MIC of 1 μg/mL.