Abstract: In order to reduce the complexity of resonance analysis and the amount of calculation,and improve the efficiency of calculation,this paper proposes an improved mode analysis method of harmonic resonance in distribution networks. According to the determinant characteristics of the admittance matrix and its variation with frequency,a curve fitting method is introduced to determine the resonant frequency of the distribution network,and then the resonant information is determined by the modal analysis method. The results of simulation analysis and test data verification show that the proposed method can significantly improve the calculation speed of harmonic resonance analysis and reduce the difficulty of harmonic analysis.