Abstract: Based on the theoretical studies on the ultrasound-induced cavitation, a numerical simulation to solve the Rayleigh-Plesset equation with Matlab was done to investigate the influence of different ultrasonic conditions including ultrasonic frequency, acoustic pressure and initial radius of cavitation bubble on the cavitation bubbling behavior in magnesium alloy melt. In addition, the effects of melt bulk temperature and acoustic pressure on the maximum temperature/pressure in collapsing bubble were also discussed. The results showed that what will benefit the ultrasound-induced caviatation are the lower ultrasonic frequency, melt bulk temperature and higher acoustic pressure, as well as the initial radius of cavitation bubble, which is equal to or less than the size that will cause resonance.