A series N-Alkylidine/Arylidene-5- Alkyl/Aryl-1, 3, 4- Thiadiazol-2-Amines have been synthesized via multistep reaction sequence. The 5-alkyl/aryl-1, 3, 4-thiadiazol-2- amine derivatives were prepared by the reaction of different aliphatic/ aromatic carboxylic acids with thiosemicarbazide in presence of catalytic amount of concentrated sulfuric acid. These derivatives were treated with different aldehydes and ketones to afford the titled compounds. Structures of synthesized compounds were assigned on the basis analytical and spectral data. All the synthesized compounds were subjected to preliminary in-vitro antibacterial activity against Gram-positive bacterial strains Bacillus Subtillis and Gram-negative bacterial strains Klebsiella Pneumoniae, Escheria coli and Pseudomonas aeruginasa. The antifungal activity of the synthesized derivatives was evaluated against Candida albicans and Aspergillus fumigates. The synthesized compounds were found to possess comparable antimicrobial activity to the standard drug.