Triazoles with different substituent groups are found to possess diverse applications in the field of medicine and industry. A series of 4-(substituted ethanoyl)amino-3-mercapto-5-(4-nitro)phenyl-1,2,4-triazoles (NU-1 to NU-15) were synthesized as novel antimicrobial agents starting from 4-nitrobenzoic acid. The chemical structures of these newly synthesized compounds were elucidated by IR, 1H NMR, 13C NMR, FAB+ -MS spectral data and elemental analysis. Their antimicrobial activities against Staphylococcus aureus (ATCC-25923), Pseudomonas aeruginosa (ATCC-27853), Escherichia coli (ATCC-8739), Bacillus substilis (ATCC-6633), Candida albicans (MTCC-227), Aspergillus niger (MTCC-3323) and Fusarium oxysporum (MTCC-2087) were investigated.