In search of novel medications that could be effective in preventing and treating diabetes, four new [Co(L)(H 2 O) 3 ] (2), [Ni(L)(H 2 O) 3 ] (3), [Cu(L)(H 2 O)] (4) and [Zn(L)(H 2 O)] (5) complexes were synthesized from 4-Chloro-2-(((3-mercapto-5-[pyridin-4-yl]-4H-1,2,4-triazol-4-yl)imino)methyl)phenol ligand (H 2 L),which is obtained by the condensation of 5-chlorosalicylaldehyde with 4-amino-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol in 1:1 ratio. The Fouriertransform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR)( 1 H and 13 C), elemental analyses, UV-visible, electron spin resonance (ESR), thermogravimetric analysis (TGA), scanning electron microscopy, energy dispersive X-ray analysis (EDAX), and X-ray diffraction (XRD) studies were used to successfully characterize the compounds. The ligand act in a tridentate manner and coordinates to the metal ions through N azomethine , O phenolic and S thiol functionalities. On the premise of their spectral and physico-analytical data; octahedral geometry for complex 2 and 3, while square planar and tetrahedral geometry for complex 4 and 5 was proposed. Theoretical calculations of the synthesized compounds have been performed by using density functional theory (DFT)/B3LYP method and parameters such as HOMO-LUMO energy values and MESP were calculated. In vitro examinations against α-amylase and α-glucosidase reveal promising results for the compounds. Nickel (II) complex(3) against α-amylase and zinc (II) complex (5) against α-glucosidase were found to be good inhibitors. Molecular docking experiments against the receptors 1BSI and 5ZCC were done to support the observation and considerable