The invention discloses a dual-power power amplifier circuit, comprising an input circuit, a bias circuit, and an output circuit. The bias circuit is formed by a NPN transistor V4, resistors R2-R4, a capacitor C3, and a digital bias circuit. The digital bias circuit comprises a field-programmable gate array FPGA, a opto-coupler isolation circuit, and a programmable digital potentiometer D1. Two output ends of the programmable digital potentiometer D1 are respectively connected with the other end of the resistor R2 and the other end of the resistor R3. The field-programmable gate array FPGA is used to generate a control signal of the programmable digital potentiometer, and the programmable digital potentiometer generates required variable resistance, to form a VBE expansion circuit, so as to adjust bias voltage of a power tube. The dual-power power amplifier circuit realizes digital design of a bias circuit, prevents crossover distortion, and realizes automatic calibration.