In this study,two-step method including hydrothermal and microwave process was used to synthesize a novel porous ZnO nanoparticles.Surprisingly,we found this ZnO could respond visible light after microwave treatment.To further verity this phenomenon,rhodamine B was chosen as the degraded model,and the photocatalytic degradation properties of ZnO with different microwave treatment time were studied.The results showed that under visible light,the as prepared porous ZnO has good degradation effect and impressive photocatalytic activity.