The invention discloses a transformer partial-discharging mode recognition method based on a singular value decomposition algorithm, and the transformer partial-discharging mode recognition method comprises training model and classification recognition process, and the method comprises the steps of firstly establishing an artificial defect experimental environment, collecting data samples, calculating statistic characteristic parameter of each sample to form a data sample matrix; conducting singular value decomposition for the sample matrix, determining an order of an optimum reserved matrix by judging whether the characteristic of the reserved matrix is obvious or not, and obtaining a type characteristic space description matrix after the dimensionality reduction and a class center description vector group; preprocessing the sample to be recognized to obtain a sample vector, utilizing the type characteristic space description matrix to linearly convert the sample vector to obtain the sample description space vector after the dimensionality reduction, and then calculating the similarity of the vector with each vector in the type vector group to obtain a classification judgment result. The algorithm is simple and high efficient, reliability for distinguishing an interference signal and a discharging signal in the partial-discharging detection can be realized, and the accuracy for diagnosing the partial-discharging mode can be improved.