Abstract: The radiation generated by gas-gap switches in the process that intense electron beam accelerator is running with pseudo load may cause the computer to be black screen. The mechanism of electromagnetic radiation induced by the triggered spark-gap switch and main switch is analyzed carefully in this paper. The charging gap of the gas-gap switches is equivalent to electric dipole, and the spatial distribution of the radiation is analyzed theoretically. The radiation signals of the triggered spark-gap switch and main switch are measured, and the result shows that the theoretical analysis is reasonable. At last, the coaxial cable is used to evaluate the interference of the radiation. At the moment that the radiation signal generates in the intense electron beam accelerator, the induced voltage in the coaxial cable reaches to nearly 3 V, which could cause inaccuracy in the measurement of other signals.