Inductively coupled plasma systems are appropriate equipments for the spheroidization processes of powder materials because they have large volumes, high purities, and axial powder injection properties. Especially the long residence times of powders inside the plasma in the reactor are another advantage of ICTPs. The fundamentals of the production of spherical ceramic powders via inductively coupled thermal plasma systems include melting process of powders in the plasma jet and free falling of them through the reactor. This theoretical study was made as groundwork of the planned study by an inductively coupled thermal plasma system. A theoretical study was made on spheroidization of powders via thermal plasma systems. In the study, nonlinear momentum and energy equations were numerically solved through a computer code written in FORTRAN. The effects of plasma gas temperature and velocity, nozzle and particle diameter, initial particle temperature and velocity, and the volume flow rate of plasma gas on particle temperature and velocity were investigated in the analysis. The results obtained via the fifth order Runge-Kutta method were given as diagrams.