The nickel (Ⅱ) complex ［Ni(PCPA)2(phen)H2O］ was synthesized by solvent evaporation method, with p-chlorophenylacetic acid(PCPA), 1, 10-phenanthroline(phen) and nickel sulfate hexahydrate as main raw materials. The crystal structure of the metal-organic complex was determined by single crystal X-ray diffraction method. The results show that complex crystallizes in the monoclinic space group P21/n with each asymmetric unit consisting of one Ni(Ⅱ) ion, two p-chlorophenylacetic acid ligands and one 1, 10-phenanthroline ligand.Fluorescence spectrum analysis shows that the excitation peak of complex is 336 nm, emission peak of complex is 393 nm. The thermal stability study shows that the complex is stable at room temperature. The magnetic measurement result shows that intramolecular antiferromagnetic interaction is observed in complex.