The invention provides an ultrasonic surgery system which comprises an ultrasonic working unit, a waveform generation unit and a control unit. The waveform generation unit is used for providing an electric signal of preset power and frequency for the ultrasonic working unit. The control unit comprises a collection module and an electric signal processing module. The collection module collects the electric signal of the output end when the ultrasonic working unit operates. The electric signal processing module is used for extracting corresponding electric parameters from the electric signal currently collected by the collection module, generating an instruction according to the obtained electric parameters and outputting the instruction to the waveform generation unit so that the waveform generation unit can adjust the output electric signal step by step, wherein the waveform generation unit adjusts the output power and/or frequency of the electric signal through the instruction. Power adjustment and frequency adjustment are carried out on the waveform generation unit at the same time according to the obtained electric parameters, and the hardware cost is reduced effectively.