The electronic structures of N, N'-bis[ (1-phenyl-3-methyl-5-oxo-4-pyrazolinyl) a-furylmethylidyne]ethylendii-mine (and -o-phenylendiimine), and their complexes of transition metals M (M=Ni, Cu, Co, Pd, Pt) have been calculated by B3LYP method of DFT. Their geometries and bonding characters are discussed, and the relationship between their bioactivities and electronic structures are also discussed from the calculated results o electronic populations and frontier orbital energies.