Abstract A general approach to analysis of class E tuned power amplifier with anti-parallel diode at switch is presented. First, the determination of diode active angle is discussed. Then the amplifier output response, along with performance evaluation, is derived and expressed in the closed form Fourier series by combining Fourier analysis and state equation technique. Applications to several amplifiers with varying param eters show that the method is fast and robust. The proposed approach affords an effective means to the exact analysis and design of class E tuned power amplifier with parallel diode at switch.