The compounds and films of La0.67Sr0.33CuxMn1-xO3（x= 0.05, 0.10, and 0.15） were prepared using the sol-gel technique and an RF magnetron sputtering method, respectively. The effect of Cu doping on the photoinduced properties of La0.67Sr0.33CuxMn1-xO3 films was investigated. Experimental results indicate that the increasing Cu doping content leads to a decrese of the insulator-metal transition temperature and an increase of the resistance. The laser irradiation induces an increase of the resistance in the metallic state. The maximum values of the photoinduced relative change in the resistance increase with increasing x, and it reaches 58.3％ at x =0.15. The intriguing mechanism of the photoinduced effect on the resistance was discussed, which may be the photoinduced electrons being trapped at a localized state outside the CuO2 planes in combination with and the lattice effect.