Wireless power transfer technology has been ready to be commercialized in consumer electronics because of the convenience of no power cable for electronic equipment and no wiring in building and medical equipment. The ever-increasing use of medical implants in the human body has led to extensive research on wireless power transmission to charge these batteries. In the meantime, wireless power transmission has been widely welcomed in recent decades with the use of ultrasonic waves due to its low level of risk and proper returns. Acoustic Energy Transfer (AET) is a relatively new method of contactless energy transfer and could be an alternative to the currently established technologies for the contactless transmission of power, such as inductive power transfer and capacitive coupled power transfer. Therefore, considering the importance of ultrasonic power transfer, in this research, an ultrasonic power transfer model from an acoustic source was investigated by a piezoelectric receiver. The acoustic source used in this study is a spherical source with a negligible radius (point source), and the receiver of ultrasonic waves is an aluminum circular plate, with two identical piezoelectric patches being completely symmetrical on both sides. The acoustic-piezoelectric coupling equations for the receiver have been extracted using the classical theory of the plate (Kirchoff theory) and Maxwell’s law. The variation of plate thickness due to the use of piezoelectric patch causes the analytical solution not to be straightforward calculating the natural frequency of the system. Therefore, the natural frequency of the receiver is calculated using the Rayleigh’s method. The system coupling equations are discretization by using the assumed modes method and the stable response of the system under loading from point source pressure for different conditions. For verifying the results of the analytical model, a finite element model is presented in the ANSYS. The results indicate that increasing the source’s ability, reducing the distance between source and receiver, and choosing a high-density environment as an ultrasonic wavelength transmission medium can increase the output voltage. High-density, low-frequency environments also make it impossible to ignore the acoustic radiation, which reduces the resonant frequency and amplitude of the output voltage. Therefore, the frequency selection for an acoustic energy transfer system is a compromise between the acoustic radiation, the transmission medium and the geometric and mechanical characteristics of the receiver. Keywords Ultrasonic power transfer, piezoelectric receiver, Pulsting Spherical Source , Kirchoff theory, Acoustic radiation