The synthesis of 4-[(arylimino) methyl-5-(4-[(aryl) methylidene] amino) phenyl)-4H-1, 2, 4-triazole-3-thiol were achieved in multi step synthesis, in first step, 4-amino benzoic acid was esterifies to ethyl-4-amino benzoate I; which was further refluxed with hydrazine hydrate 99% to obtain 4-aminobenzoic acid hydrazide II. Compound II was agitated with ethanolic KOH and CS₂ to produce inorganic salt potassium-4-aminophenyl-dithiocarbazate III; later compound III was refluxed with hydrazine hydrate 99% to produce 4-amino-5-(4-aminophenyl)-4H-1,2,4-triazole-3-thiol IV. In final step; compound IV were treated with aromatic aldehydes to produce title compounds 4-[(arylimino) methyl-5-(4-[(aryl) methylidene] amino) phenyl)-4H-1, 2, 4-triazole-3-thiol Va-n. All the title compounds were identified by FT-IR, ¹H-NMR, GC-mass spectroscopy data, and elemental analysis; have been screened for in-vivo antibacterial activity against organisms like E.coli. K. pneumonia, S. aureus, and B. subtilis as well as in-vitro antifungal activity against A. niger and C. albicans. In-vivo antimicrobial evaluation reveals that the most potent broad spectrum compounds Va, Ve, Vf, Vg, Vi, Vj and Vm were found to be significant agents in comparison with standard Norfloxacin and Fluconazole.