Ferrite chokes are often applied to suppress electromagnetic interference (EMI) in power converters. In this paper, an improved ferrite choke RLC model and its parameters determination method are proposed. The improved ferrite choke RLC model can overcome the limitation of the existing RLC model in the low frequency band, and the proposed parameters determination method can calculate the values of RLC parameters more accurate according to curve fitting of the ferrite choke datasheet. The effectiveness of the improved ferrite choke RLC model is verified by simulation based on a PWM rectifier, and the accuracy of the parameters determination method is verified by the impedance fitting results. The proposed ferrite choke RLC model and parameters determination method in this paper can provide ferrite choke choosing guidance for power converters in engineering application.