As afull-featured power electronic equipment, unified power flow controller (UPFC) need fault ride-through ability. UPFC series and parallel inverter parts will withstand the impact of failure duringAC line fault.And for instantaneous fault of the line, theUPFC needstocontinue to run after theline fault is cleared.Based on the structure and fault characteristics of UPFC，the processing strategy of UPFC in the case of AC system failure is put forward, so that it has the fault ride-through ability.The UPFC parallel side can run continuously during the fault by use optimization control strategy. And the serial side can exit and restart quickly, with the coordination of UPFC control and protection strategy, line protection and reclosing logic.The rationality of the strategy is verified by manual short circuit test and the actual system fault test during the operation of Nanjing UPFC demonstration project.