Reduction of molten iron oxide with Ar-H₂ plasma was studied using a DC 15KW power sourse. 50g of sample was melted by Ar plasma and reduced in a stream of Ar-H₂ gas, the flow rate of which was 17ℓ/min. Degree of reduction (R) was reached as much as 95% within 12 min by Ar-H₂(14%) plasma, and it was linearly propotional to both the reduction time and the partial pressure of hydrogen. Additives such as CaO, MaO, SiO₂ and A1₂O₃charged in the range of 1-20% showed only trivial effects, however in case of charging serpentine which contained same ratio of acid and basic components, there was a tendence to increase in the reduction degree Kch. Reduction rate constant was calculated, as a function of hydrogen concentration in the Ar-H₂Plasma, the 0.512. Reduction rate and gas utilization % were increased with the increase in plasma temperature, dissociation of H₂and gas ionization such as H→H＾+ + e.