$MgH_2$ was synthesized by hydriding chemical vapor deposition (HCVD). In this study, we examined the hydrogen storage property of $MgH_2$ synthesized by HCVD. The results of pressure-composition-temperature (PCT) measurement showed that the HCVDed $MgH_2$ reversibly absorbed hydrogen as much as 6 wt%. Each hydrogenation rate was very greater than the conventional alloy methods. The reason was that the particle size made by HCVD was small as approximately 1 ${mu}m$. The PCT of $MgH_2$ made by HCVD methode was similar to a commercial $MgH_2$. The ${Delta}H$ and ${Delta}S$ value are respectively -76.8 $kJ/mol{cdot}H_2$ and -137.4 $kJ/mol{cdot}H_2$. Mg made by HCVD methode was activated easily than commercial Mg. Also the initial reaction rate was faster than that of commercial $MgH_2$. 70% of the total storage were stored during 400s.