How to ensure the stability of the output power and frequency of ultrasonic vibration power supply is a hot spot in the research of power supply technology. The design of ultrasonic vibration power supply control model based on BP neural network is applied to guarantee the stability of output frequency and power of ultrasonic vibration, and improve the working efficiency of ultrasonic aided casting system. Verified by the system simulation and experimental results, the output area of frequency of new ultrasonic vibration power supply is from 19.259 kHz to 20.086 kHz, the average amplitude of ultrasonic is 15.93 microns, and the area of output power is from 1.073 kW to 1.203 kW in the experiment of aluminum alloy melt casting under 730 Centigrade. Further, the average size of melt grain is 143.63 microns, and the grain size is uniformed. The results show that the new ultrasonic vibration power supply control model can improve the output power and frequency accuracy of power, which is helpful to the stability of ultrasonic vibration power supply and enhance the quality of aluminum alloy casting.