In order to improve the photocatalytic degradation ability of TiO₂, TiO₂-g-C₃N₄-ZIF-67 catalysts were prepared by Co-doping g-C₃N₄, ZIF-67 with TiO₂ by sol-calcination method. The effects of g-C₃N₄, ZIF-67 on the morphology and structure of TiO₂ were investigated based on XRD, XPS, SEM, and UV-vis DRS characterization; and the photocatalytic activity of TiO₂and its composites was evaluated by the degradation rate of methyl orange. The results showed that the band gap of g-C₃N₄ doped TiO₂ could be reduced from 3.04 eV to 2.45 eV compared with that of undoped samples, and continued to be doped with ZIF-67, and the band gap was further reduced to 1.91 eV after doping, among which TiO₂-g-C₃N₄-ZIF-67-2 corresponding to a cobalt mass content of 21.50% had the highest activity and was able to degrade 79.92% of methyl orange in 40 min and 90 min. of methyl orange at 40 min and 89.50% of methyl orange at 90 min. The Co-doped samples had good cycling stability, and the TiO₂-g-C₃N₄-ZIF-67-2 catalyst had a degradation rate of 58.86% after three cycles.