Highly spherical powders were successfully produced with a radio frequency plasma system. Six influential parameters, namely position of the inlet nozzle, plasma plate power, chamber pressure, particle size distribution of raw materials, the feeding rate and the flow rate of the carrier gas were changed respectively and the spheroidization ratio was counted with the help of SEM images. The phase structure and morphology of the powders were investigated by XRD and SEM. Morphologies of the surface and cross section indicate that the spherical particles are dense with a relatively smooth surface. Fluidity and bulk density were both improved to be suitable for practical application. Spheroidization ratio as high as 99% has been reached when the position of the inlet nozzle is 12.5cm, the chamber pressure is 14.7psia, the powder feeding rate is 1.742g/min, the plasma plate power is 27.2kW and the average size of raw particles is around 38~63μm.