Graphene quantum dots (GQDs) have been explored in recent years for electrochemical applications with considerable potentials. Here, we present GQD-doped CuCo2S4 nanocomposites through two-step hydrothermal process for supercapacitor electrodes. The surface of CuCo2S4 nanosheets changes from smooth to particles-accumulative shape, which assists the electrochemical cycling processes as well as the ion diffusion and charge transfer kinetics for improved supercapacitor performances. As a result, GQD/CuCo2S4 electrodes demonstrate a specific capacitance of 1725 F g(-1) under a current density of 0.5 A g(-1) and a cycling life of 10,000 cycles by retaining 90% of the energy storage capability. As such, this work extends the potential of GQDs in electrochemical applications by means of morphology change of CuCo2S4 nanosheets.