Abstract: As key primary equipment for fault current interruption and load switching, the operational status of 110 kV circuit breakers is vital to power supply reliability. Focusing on three typical fault types, namely insulation degradation, operating mechanism failure, and contact damage, this paper establishes a technical system that encompasses condition monitoring, comprehensive health assessment, and disassembly and overhaul. An engineering case involving a circuit breaker fault at a 110 kV substation verifies the effectiveness of the assessment model. The paper also proposes an integrated fault prevention system combining installation quality control with misoperation prevention during operation and maintenance. The proposed approach provides a systematic technical reference for lean operation and maintenance of 110 kV circuit breakers.