The invention belongs to the technical field of power system line fault judgment, and particularly relates to a line fault judgment method based on wavelet analysis and a support vector machine. The method comprises steps: firstly, fault current signals in a wave recording system are extracted, and the wavelet analysis technology is adopted for extracting and analyzing feature information of the fault current signals; then, a wavelet energy entropy theory is used for decomposing the fault current signals, an energy entropy value corresponding to each phase of current is calculated, and zero-sequence current is combined for building a four-dimensional feature vector for transmission line fault classification; and finally, a two-layer classification model is used for specific fault judgment. The judgment method comprises a linear classification module and a nonlinear classification module, wherein linear classification is initial classification on data samples according to the two-layer classification structure of the zero-sequence current and threshold parameters; and on the basis, according to data features for transmission line small sample fault, the support vector machine is used for nonlinear classification on multiple kinds of fault data, and transmission line fault judgment is finally realized.