In this paper, a kind of class-DE soft switch for high-power and high-frequency induction heating power supply based on full-bridge inverter is proposed in order to improve the working frequency of IGBT. The proposed class-DE full-bridge inverter circuit is analyzed. The circuit is divided into four states, and the circuit and waveform of each state is analyzed. The full-bridge inverter works in 20kW, 60kHz series resonant state. The experimental results show that the class-DE soft switch can improve the operating frequency of IGBT.