Ultrasound-facilitated particle breakage has been proven to be a good technique for size reduction. However, because of the difficulties associated with the solution of population balance equation (PBE), there has been little attention on the estimation of kinetics of this process. In this paper an attempt has been made to develop a generic approach for solving PBE with a given particle size distribution (PSD) data to estimate the breakage kinetics. For this purpose, discretization technique along with gPROMS parameter estimation tool was used. This method was found to be a comprehensive method for the estimation of breakage kinetics in general and was subsequently used for the estimation of ultrasound-facilitated breakage kinetics, using a simple model system. Potassium nitrate (KNO3) particles suspended in toluene was used as model system, and the effect of induced power on breakage strength was studied. The data obtained were used for the estimation of specific breakage rate with different particle size distribution function. The distribution function, for which simulated PSD was found to match with the experimental PSD, was considered for deriving energy-size reduction law.