Abstract: The LLC resonant converter has significant merits, such as high conversion efficiency and soft switching characteristics. However, in the field of DC charging, the wide output voltage gain requires the operating frequency of the LLC resonant converter to cover a wide range, which cause the loss of the conversion efficiency, the complex design of magnetic components, and limited light-load regulation, etc. In this paper, an LCL-T/LLC resonant converter with a multiplexing resonant inductor for the on-board charging of electric vehicles is proposed. On the secondary side of the transformer, the resonant inductor opreates with the LCL-T resonant tank for the constant current (CC) charge of the battery. The inherent characteristic of the LCL-T can limit the range of the operating frequency. While for the constant voltage (CV) charge, the resonant tank is modified by the auxiliary branch, and the resonant inductor opreates in the LLC converter, which works as a CV source. As the resonant inductor is placed on the secondary side of the transformer, the core loss during the dead time is reduced and the conversion efficiency is improved. The operation mode and the DC gain characteristics of the proposed converter are analyzed. Moreover, the design procedure of key parameters is provided. In the end, a 3.3 kW, 400 V/ 330 V experimental prototype is built to verify the feasibility and effectiveness of the proposed resonant converter and its control method.