kinetic study on the preparation of iron powder by hydrogen reduction of ferrous chloride vapor has been carried out both experimentally and theoretically. For the preparation of iron powder, ferrous chloride was vaporized and transported to a reaction zone by Ar gas used as carrier. Ferrous chloride vapor and hydrogen were mixed and subject to a reduction reaction at high temperature to produce iron powder and HCI gas. Iron powder was collected with organic solvent at the end of reaction zone and HCI gas was also absorbed in a caustic soda solution to determine the conversion ratio of ferrous chloride. For the development of rate equations, a 1st-order reaction and equilibration of ferrous chloride vapor with Ar gas were assumed. According to the results, the rate constant, k could be expressed as k=7,879exp(?53,840/RT)dm 3 /mole.sec and the activation energy was found to be 53.84kJ/mole. From TEM observation, the particle size distribution of iron powder produced was found to be in the range of 0.1 1.0μm which was not significantly influenced by reaction temperature or gas flow rates.