The invention discloses a dual-band high-efficiency power amplifier matching circuit for a GaN power device. The dual-band high-efficiency power amplifier matching circuit comprises a matching transformation module, a fundamental wave matching module, and a secondary harmonic wave reactance matching network, wherein the matching transformation module and the fundamental wave matching module are serially connected; an output end of the secondary harmonic wave reactance matching network is connected between an output end of the matching transformation module and an input end of the fundamental wave matching module; an input end of the matching transformation module is connected to an encapsulated output end of a transistor; an output end of the fundamental wave matching module is connected to a load; and the secondary harmonic wave reactance matching network is a first secondary harmonic wave reactance matching network used for transforming a short-circuit state of a secondary harmonic wave into an open-circuit state and used for transforming the open-circuit state of the secondary harmonic wave into the short-circuit state. According to the matching circuit of the invention, the structure is simple, the implementation is easy, and the impedance matching of two bands can be implemented simultaneously; and thus, the requirement of working at dual bands simultaneously is implemented, and an amplifier has relatively high working efficiency.