Water atomization of metal powder is a process whereby a series of water jets impinging on a stream of liquid metal creates small droplets. As currently known to researchers, formation of metal droplets is affected by apex angle and molten metal properties, which in turn influence the final particle size distribution. However, manipulating and controlling the range of particle size distribution remains difficult in the industry. Therefore, the process from jet impingement to droplet formation was investigated using analytical methods and computational fluid dynamics simulations. A multiphase axisymmetric computational fluid dynamic (CFD) domain was developed to simulate the liquid metal stream-water jet interaction under various operating conditions. The breakup behavior was observed and explained by analyzing the influence of apex angle on water jet momentum transfer, total kinetic energy transfer, effect of surface energy, and vapor formation phenomenon.