A series of sonofragmentation experiments were performed by varying the sonication time and ultrasonic amplitude in order to investigate and simulate the two-dimensional ultrasound-assisted breakage of delta-form of pyrazinamide crystals using Monte Carlo (MC) method. An event driven constant number MC algorithm is presented to predict the evolution of two-dimensional size distribution of the product crystals. The MC simulations were performed by considering the breakage across the width of the particles and restricting the randomness of the break up point to a particular region along the length axis. The results obtained are in excellent agreement with the experimental observations. The proposed MC method reproduces both mode and span of the experimental size distribution with remarkable accuracy for all the cases. Further, it has only one tuning parameter depending on the ultrasonic amplitude. A graphical correlation has been obtained for selection of this tuning parameter for a given ultrasonic amplitude. Thus the proposed MC approach can be used to obtain quantitative view about the effect of sonofragmentation of two-dimensional plate-like crystals. (C) 2019 Elsevier Ltd. All rights reserved.