Abstract:The coordination chemistry of transition metal complexes has been progressing at a tremendous pace. These complexes were finding use in the field of homogeneous catalysis, analytical chemistry and biological system. The presence of thiocyanto group in mixed ligand coordinated complexes of transition metal was reported to have an ability to influence the biochemical behaviour of the complexes. Complexes of MM'(SCN) 4 (M = Co 2+ ; M' = Cd 2+ , Hg 2+ ) with N, N'-bis (benzylidene) -1, 2, phenylenediamine Schiff base of molecular formula [MM'(SCN) 4 (BENDAMB) (1, 2)] have been synthesized and characterized by elemental analyses, molar conductance magnetic moment, IR, electronic and 1 H NMR spectral studies. The softness parameter TEn ≠ of complexes have also been calculated to derive the binding side of the thiocyanate ligand. The insecticidal activity against Red cotton bug (Dysdercus koenigii) and antifungal activity against A.Flavus and F.Solani of complexes also been investigated and was compared with solvent and Schiff base.