Abstract: A design of a broadband high-efficiency Doherty power amplifier with efficient integrated filtering characteristics is proposed. The carrier power amplifier is designed using extended continuous class F, and a coupled microstrip line filter structure is used for post matching design. The terminal of this structure is composed of microstrip lines cascaded together to enhance the out of band suppression effect. This structure not only improves efficiency but also widens the frequency band. Doherty power amplifier is designed and implemented using 10 W gallium nitride high electron mobility transistors devices, and its broadband characteristics are verified. In 1.6 GHz~2.4 GHz, the Doherty power amplifier achieves a saturation gain of 7.7 dB~9.9 dB and a saturation power of 43.1 dBm~44.7 dBm, the drain efficiency at 6 dB output backoff and saturation is 50.1%~58.8% and 59.9%~73.3%.