In order to solve the problem of failure of control system of terminal guided ammunition, this paper proposed a method of HI-FMECA for reliability analysis of the control system of terminal guidance projectile. According to the structure and principle of the control system and on the basis of the comprehensive methods of FTA and FMECA, the HI-FMECA method was used to analyze the failure of the terminal guidance projectile. Through the FMECA analysis of the bottom events of the control system, the failure reason, and failure influence, and severity level were determined, and the key failure mode of the terminal guidance projectile control system was obtained. The results showed that this method was practical. It provided a certain basis for the control system of terminal guidance projectile and life extension work of shells