The reactor trip circuit breaker (RTCB) is a critical component in the reactor protection system (RPS) of nuclear power plants, and its reliability directly impacts whether the reactor can achieve and maintain a stable and safe state. This paper summarizes the failure modes and causes of RTCB and compares the design differences in the connection methods of RTCBs among domestic M310 units, CPR units and HPR1000 units. It uses the fault tree analysis (FTA) method to analyze the spurious trip and failure-to-open of RTCB of different structures, evaluates the impact on core safety in consideration of the current reliability of RTCB, and discusses the diverse designs applied to prevent common-cause failures. This research provides technical references for engineers engaging in RTCB-related tasks in nuclear power plants.