When L-ornithin-aspartate was crystallized by drowning-out method in a turbulent agitated semi-batch reactor, the effects of the crystallization conditions, such as the feed concentration, alcohol flow rate, and agitation speed, on the agglomeration and breakage of the L-ornithine-aspartate particles were investigated. The mean particle size of the L-ornithine aspartate in the product suspension was reduced when the agitation speed and holding time were increased. However, a higher feed concentration enhanced the particle agglomeration and nucleation, resulting in larger mean particles. The dependency of the mean particle size on the crystallization conditions was depicted using a power law model of a Camp number, which matched with the experimental data. Prior to the drowning-out crystallization, the solubility of L-ornithine aspartate in water-alcohol mixtures was examined and correlated as a function of the alcohol composition. Due to the inhibitory effect of alcohol on the intramolecular interaction between the solvent and the solute, the solubility was dramatically reduced when increasing the amount of alcohol in the mixture.