A method of manufacturing a powder having a high surface area is provided. According to the method of manufacturing a powder having a high surface area, a metal electrolyte in which metal ions of different kinds of first metals are dissociated is prepared. Subsequently, a metal alloy powder formed of the first metals is formed by soaking a second metal having a higher reducing power than the first metals in the metal electrolyte to induce a first spontaneous substitution reaction. Therefore, it is possible to form a powder having an improved specific surface area.