Organotin(IV) complexes [R2SnL1, R2SnL2); R= Me, Et, Bu and Ph] have been synthesized by reaction of diorganodichlorotin(IV) with biological potent Schiff base ligands 5- hydroxymethyl-4-[(2-mercapto-phenylimino)- methyl]-2-methyl-pyridin-3-ol (H2L1), 4-[(5- chloro-2-mercapto-phenylimino)-methyl]-5-hydroxymethyl-2-methylpyridin- 3-ol(H2L2) derived from pyridoxal hydrochloride with 2-aminothiophenol and 2-amino-4-chlorothiophenol respectively. The geometry of these compounds has been proposed on basis of elemental analyses, molar conductance and spectroscopic techniques (IR, electronic, 1H, 13C and 119Sn NMR). On the basis of these studies it revealed that Schiff base ligands acted as ONS donor system and coordinated to tin atom in tridentate fashion with trigonal pyramidal geometry around tin atom. To compare the biopotency of these complexes, Schiff base ligands and their complexes were also tested for in vitro antimicrobial evaluation against some pathogenic fungi and bacteria. Enrichment was observed in biological activity of ligands on coordination with tin atom