A simple, broadband and efficient Class E power amplifier operating in the C-band was designed in a 025 (m GaN HEMT process. To address the problem of large RF choke area in the design of monolithic microwave integrated circuit (MMIC) power amplifier, a finite DC-feed inductance instead of RF choke inductance was used to suppress the effect of the transistor parasitic parameter Cds on the maximum operating frequency. Moreover, a low Q mixed parameter matching network was adopted to match the optimal impedance of the input and output of the power amplifier circuit to the standard impedance of 50 Ω. The post-layout simulation results show that the power-added efficiency is 51309% to 58050% in the 41-49 GHz operating frequency band, with an average gain greater than 11 dB and an output power greater than 41 dBm. The size of layout is 27 mm×14 mm.