In order to reduce the adverse effect caused by single-phase broken-line fault to the power supply quality, a systematic protection method is proposed for the single-phase broken-line fault of the distribution line. Using circuit principle and neutral point voltage shift theory, this paper analyses and summarizes the features of the voltages at both ends of the fault line and the current flowing through the fault line when single-phase broken-line fault with or without a grounding fault occurs. The judgement and protection method that consists of the current criterion and the voltage criterions for single-phase broken-line fault is proposed. The methods for judging the fault type and the fault location are studied based on the voltage criterions. The influences of abnormal operating status like asymmetry operation and transformer disconnection on the criterion and the corresponding protection methods are analyzed. Simulation is carried out in PSCAD/EMTDC, which ensures the correctness of the theoretical analysis and the effectiveness of the protection methods. This work is supported by National Natural Science Foundation of China (No. 51877126).