We have studied on the effect of the temperature and reaction time by investigating the various temperatures and reaction times in the reduction of molybdenum oxide (MoO3) to molybdenum(Mo) powder in hydrogen gas. And we have also studied on the effect of the reaction of reduction according to the various hydrogen gas flow rate. We have surveyed the reduction from molybdenum oxide to molybdenum powder in hydrogen gas and have checked in the two temperature ranges, one is from 400℃ to 600℃ and the other is from 700℃ to 900℃. We have found reaction ratio of molybdenum oxide was increased with increasing temperature, and was also increased with increasing reaction time but hydrogen gas did not have an influence on the reduction ratio of molybdenum oxide. We have examined molybdenumpowdersfabricatedbyball-milled for two hours, by using with an X-ray diffraction(XRD) and a scanning electron microscopy(SEM).