Two complexes [Cu(pic)(im)(Him)]·2H₂O (1) and [Cu(2,6-pda)(2-Hmim)(H₂O)₂](2-Hmim) (2) were synthesized using 2-pyridine carboxylic acid and (2-Hpic) pyridine-2,6-dicarboxylic acid (2, 6-H₂pda) as main ligand, imidazole or 2-methylimidazole as auxiliary ligand. The complexes were characterized by elemental analysis, X-ray powder diffraction, infrared spectroscopy and thermogravimetric analysis. Nano-copper oxide was prepared with the copper(Ⅱ) complexes as precursors and their photocatalytic degradation of methylene blue (MB) was investigated. The experimental results show that the copper oxide can effectively degrade MB dye and has good stability. In addition, the antibacterial properties of the copper(Ⅱ) complexes were studied, and it is found that they have certain antibacterial effects on both Gram-positive and Gram-negative bacteria. In particular, the inhibition zone diameter of the complex 1 against E. coli reaches 16 mm, and the complexes show high drug sensitivity to Gram-negative bacteria.