Abstract: Silicon carbide(SiC) switching devices will produce strong electromagnetic radiation interference in DC/DC converter. In order to optimize the internal structure of the converter and achieve higher power density, a prediction method of electromagnetic radiation interference in SiC DC/DC converter is proposed in this paper. In this method, the inner conductor of the converter is divided into vertical conductor and plane rectangular conductor, and the mathematical model of electromagnetic radiation interference caused by the two conductors in space is established. Based on SPICE model of SiC switch device, the circuit level simulation of DC/DC converter is established, and the current spectrum of each branch in the converter is obtained as the excitation source of EMI model. Finally, three-dimensional finite element simulation is carried out by Maxwell software, and the simulation results are basically consistent with the model results in this paper, which proves the correctness of the proposed method.