Abstract: In order to explore the spatial structures of Schiff bases and their complexes,two new complexes,CoL₂(H₂O)₂·5H₂O and Cd(L)(HL)(H₂O) ·ClO₄·H₂O _n(HL = 4-N-(2'-pyridylimine) benzoic acid; L = 4-N-(2'-pyridylimine) benzoic acid radical),had been synthesized by stewing method and structurally determined by X-ray diffraction analysis. The result shows that the first complex crystallizes in monoclinic system with space group P2₁/c and the second complex crystallizes in orthorhombic system with space group Pbca. The structure analysis shows that the first complex is a mononuclear molecule and the metal center adopts a six-coordination geometry formed by four N atoms from two ligands and two O atoms from two H₂O molecules; the second complex is one-dimensional chain structure and each metal center adopts a seven-coordination geometry formed by four N atoms and two O atoms from L and HL,and one O atom from H₂O.