In this paper, a method of power supply network topology identification based on iterative principal component analysis (IPCA) and voltage correlation analysis (VCA) is proposed. This method is based on the principle of conservation of electric energy, that is, the electric energy measured by the superior electric meter is equal to the sum of the electric energy measured by the subordinate electric meters connected below it, and the topology of the power supply network is modeled as a linear model among the electric energy of each electric meter. IPCA is used to estimate the model constraint matrix and calculate the error covariance matrix of the electric energy measurement value. The error covariance is used to modify the model constraint matrix. Finally, the regression matrix is obtained according to the model constraint matrix, and then the correlation matrix is obtained to identify the low-voltage power supply network topology.