To get single-layer of graphene, exfoliating fully intercalated graphite oxide into single- layer graphene oxide is one of the important factors. In this paper, graphite oxide prepared by the Improved Hummers Method, and ultrasound was added to the Low-temperature Reaction of this oxidation process to improve the efficiency of intercalation. Then the obtained graphene oxide was dispersed with surfactant and reduced with Hydrazine Hydrate. XRD patterns indicated that the layer distance of graphite oxide did increased at the aid of the ultrasound, and the obtained reduced products were single- and few-layer. FT-IR analysis further confirmed the preparation of graphite oxide and graphene.