Abstract: This paper considers a case of single event impinging the RTU, one of the most vulnerable device on the satellite, to show the influence of the single particle event on the satellite commands. The RTU, as a typical electronic device on the satellite, contains the SEE sensible components such as the processor and the SRAM. In this case, the single particle events are successfully enacted in the working state of the RTU in an appropriate rate. The working state of the RTU under single particle event attack is obtained, and the effectiveness of the RTU's anti-SEE design is well verified. The rate of command loss and command error is calculated from the test data. The result is helpful for analyzing the inflight faults and the anti single particle design.