Transition metal oxides are ideal electrode materials used for supercapacitors.However,the synthesis of transition metal oxides suffers from drawbacks such as high reaction temperature and energy consump-tion.Herein,we report the synthesis of sea urchin-like Co3O4-NiO composites supported on graphene oxide (GO) using a hydrothermal method followed by calcination with a low temperature (250 ℃).The obtained Co3O4-NiO/GO composite demonstrates a high specific capacitance of 883 F g-1 at 1 A g-1.Furthermore,upon coupling with an activated carbon (AC) positive electrode,an asymmetric cell of Co3O4-NiO/GO//AC exhibits outstanding stability reflected by the high capacitance retention of 82％ at a high current density of 10 A g-1.The excellent electrochemical properties of the composite may be attributed to the good synergistic effect of Co3O4 and NiO,as well as the assembly of Co3O4 and NiO into a sea urchin structure,which results in increased electron conductivity and more exposed electroactive sites leading to the promotion of the Faradaic redox process.