The invention relates to a preparation method for an in-situ synthesis three-dimensional graphene/one-dimensional carbon nanotube-supported copper nanoparticle material. The preparation method comprises the following steps that (1), mixed solution preparation is performed, specifically, copper nitrate powder, anhydrous glucose powder and sodium chloride are fetched and dissolved in a certain amount of deionized water to obtain a uniform mixed solution; (2), freeze-drying is performed to obtain mixed powder; (3), in-situ synthesis of three-dimensional graphene is performed, specifically, the mixed powder obtained in the step(2) is placed into a quartz ark, then the quartz ark carrying the mixed powder is placed into a tube furnace middle portion constant temperature zone, the temperature israised to 730-750 DEG C in a hydrogen atmosphere, after heat preservation is performed for a while, hydrogen is closed, a mixed gas of acetylene and argon at a given flow rate is introduced in, the heat preservation is performed for a while again, the acetylene is closed, the furnace is cooled to room temperature in an argon atmosphere, and a Cu@GN/CNTs composite material taking the sodium chloride as a template is obtained; and (4), the sodium chloride template is removed.