Abstract: In order to evaluate the electromagnetic protection performance of radio fuze, an experimental method and operation process were proposed for continuous wave electromagnetic radiation effect. The radiation effect was studied experimentally for a kind of decimeter-wave radio fuze in different radiation ways, including single-frequency radiation, sweep frequency radiation and amplitude-modulated radiation. The change laws of the critical firing field were obtained for the fuze in three radiation ways, and the interference mechanisms were also analyzed. The results show that, there is an upper limit in the firing field of radio fuze induced by single-frequency electromagnetic radiation, and a sudden firing possibility of the radio fuze can enhance by single-frequency radiation, sweep frequency radiation and amplitude-modulated radiation in turn, the least critical firing field is 0.38 V/m merely. Based on the above results and the interference mechanism of continuous wave electromagnetic radiation, an electromagnetic reinforcement method for radio fuze and an efficient interference method to radio fuze are put forward.