Magnetization curve was strongly nonlinear function. It was important to improve the accuracy of the magnetization curve fitting for the model of electrical equipment containing ferromagnetic material. Therefore, a method of magnetization curve fitting based on PSOLSSVM algorithm was proposed. The method used particle swarm optimization algorithm to solve the LSSVM parameters selection problem. The simulation results showed that PSOLSSVM algorithm could obtain optimal LSSVM parameters and the magnetization curve used PSOLSSVM algorithm has high fitting accuracy.