The solid complexes of Pd(II),Pt(IV),V(III) and Ru(III) with Schiff base ligand(HL) derived from heterocyclic compounds 3-acetyl-6- methyl-(2H)-pyran-2,4(3H)-dione (Dehydroacetic acid) and 4-aminoantipyrine were synthesized and characterized by elemental analysis,IR,1H-NMR , molar conductance, magnetic moment, UV-Vis and thermal analysis (TG/DTG). The magnetic moment and spectral data suggest that the V(III)and Ru(III) complexes have octahedral geometry while the Pd(II)and Pt(IV) complexes have square planar geometry .The ligand coordinated to the metal ions as tridentate, with ONO donor sites. The thermal behavior of these complexes shows that the complexes loose of lattice and or coordination water molecules in the first step and is followed by decomposition of the anions and ligand moieties in the respective steps. The ligand and their metal complexes were also screened for their antibacterial activity against bacterial species as well as fungi. The activity data show that the metal complexes to be more potent antimicrobial than the parent ligand.The antibacterial activity follow the order:HL