To solve the application of electromagnetic time reversal (EMTR) theory in fault location of uneven power lines, a location algorithm is proposed: It is to install viewpoints on both sides of the circuit to extract temporary fault signals; Performing time reversal processing on the extracted transient signal; The lossless mirror circuit is constructed and the inverted transient signal is injected into it; When the current propagates in the mirror line, it produces energy focus, and the maximum energy is the fault point. Since the inversion process is carried out in the lossless mirror line, it will produce ranging error. The result is corrected according to the line parameters and fault boundary conditions, and finally the location of the actual fault point is obtained. The simulation model is built in PSCAD/EMTDC for verification. The results show that the EMTR theory can be applied to non-uniform media, and the transition resistance and fault type do not affect it, and it has high ranging accuracy.