A novel composite material PIL@TiO2 was synthesized by sol-gel method using zwitterionic ionic liquid (1-(3-sulfonic group) propyl-3-ethylimidazole). TiO2 was uniformly loaded on PIL (poly(1-(3-sulfonic group) propyl-3-ethylimidazole)). The large specific surface area, unique microspore structure, negative effect, and synergistic effect were caused by PIL. PIL@TiO2 can effectively improve the separation efficiency of the electron-hole photogeneration. The electron-hole pair and (OH)-O-center dot play an important role in the photo-degradation. The structure of dye molecule is also an influencing factor for the degradation capacity. After five cycle experiments, PIL@TiO2 still exhibited excellent photocatalytic efficiency to dye molecules and its photocatalytic efficiency is better than that of P-25 (nanoscale TiO2) in the methyl orange and Rhodamine B solutions.