A ZVZCS(Zero-Voltage and Zero-Current Switching) Three-Level DC/DC Converter using Primary Coupled Inductor is proposed. The proposed converter presented in this paper used a phase shift control with a flying capacitor in the primary side to achieve ZVS for the outer switch. A primary auxiliary circuit, which consists of two small diode and one coupled inductor, is added in the primary to provides ZVZCS conditions to primary switches, ZVS for outer switches and ZCS for inner switches. Many advantages including simple circuit topology high efficiency, and low cost make this converter attractive for high power applications. The principle of operation, feature and design considerations are illustrated and verified through the experiment with a 2kW 40kHz IGBT based experimental circuit.