Abstract: In this paper, a modified envelope-domain Volterra series model based on feedback structure is introduced. For the sake of reduction of model complexity and time cost during computation process, the MVS model is simplified by analyzing physical characteristics of power amplifiers and omitting those trivial components in the model. A 10 W WCDMA power amplifier is simulated in ADS for measuring input and output waveforms which are used in model extraction and verification for both MVS model and tradition MP model. Simulation results show that the MVS model can describe both dynamic nonlinearity and memory of power amplifier very well because its NMSE is 3 dB less than that of MP model, and at same time greatly decreases model complexity.