Abstract: To solve the problem that mine high-voltage power network with neutral grounded by arc suppression coil is difficult to select line,the paper proposed a method of transient component line selection leakage protection based on wavelet analysis.The method uses steady value off-limit and break variable off-limit of zero-sequence voltage to judge if power network has leakage fault,uses detection principle of wavelet singularity to locate fault time accurately in order to sample transient component of each line precisely,and makes wavelet packet transform for sampled transient component to calculate line selection criterion formed by wavelet packet coefficient and make leakage line selection according with the criterion.The simulation experiment showed that the method has high sensitivity and accurate line selection,which has certain feasibility.