In view of the fact that the electrochemical capacity of graphene (G) prepared by the Hummers method is not high, a high pressure homogenization treatment was used to modify the structure of graphene oxide (GO) to obtain G with better electrochemical performance. The obtained samples were characterized by UV-Vis spectrum, X-ray diffraction, Raman spectrum and nitrogen adsorption desorption tests. The results show that high pressure homogenization treatment can reduce the number of GO layer, and thus make the GO solution have better dispersion and homogeneity. At the same time, the defect degree of the obtained GO is improved. After further reduction, its electrochemical capacity performance has been greatly improved (from the 80 to 188F.g(-1) in organic electrolyte) when it was assembled into supercapacitor, indicating that high pressure homogenization treatment can effectively improve the GO (G) electrochemical energy storage performance.