This paper presents a Three-port current-source bidirectional resonant converter. The converter achieves zero-voltage switching (ZVS) due to the presence of a parallel resonant tank circuit, a combination between parallel inductors and capacitors. Moreover, it has reduced output current ripple and reduced power losses in the transistors if compared with a voltage source topology. The conversion occurs with self-oscillating switching technique or with forced switching in a predetermined frequency range without losing the ZVS conditions. Due to the high frequency transformer that allows a high voltage ratio between the ports, the converter applications includes different energy storage systems that require bidirectional power flow capability, such as hybrid vehicles. A design procedure to select the converter parameters and simulation results are presented to validate the converter operation principle.