Abstract: When the devices are irradiated with the system at the transient dose rate, many of them will work at the state that all of the input signal, power supply and the photocurrent are out of the designed state. This transient effects can not be found by irradiating the device only. So transient radiation effects with -ray on an electronics system, composed of DC/DC, CPU, FPGA, et al, were investigated. The gamma pulse width was 20 ns and the dose rate was in the range of 2.8105 to 1.7107 Gy (Si)/s in the experimental study. And the function of the system and many parameters of the main devices were tested. The result of experiments showed that some of the test devices were disrupted by low level of transient radiation, but the system work was not disturbed. While the dose rates increased, all of the devices were disrupted and the system function failed. The signal originating from the transient ionizing radiation transferring from the input to the output of the device was observed.