In this work, the nanosheet-assembled SnS2 microspheres were synthesized through a solvothermal method, and the catalytic activities of the microspheres were investigated by J-V and power conversion efficiency tests as counter electrodes in dye-sensitized solar cells. The cell showed an energy conversion efficiency up to 6.4%. To further improve the power conversion efficiency of the counter electrode of the microspheres, different amounts of reduced graphene were added into the microspheres by simply physical mixing. With the addition of 6 wt% reduced graphene, the short-circuit current density, open-circuit voltage and fill factor were 15.18 mA cm(-2), 775 mV, and 63.4%, respectively. More important, the conversion efficiency reached 7.46%, which is approximately 17% higher than that of the cell with pure SnS2 microspheres as counter electrode. Compared to conventional materials used in dye-sensitized solar cells, SnS2 microspheres have the advantages of facile synthesis, low-cost and high efficiency with graphene assistance. (C) 2015 Elsevier B.V. All rights reserved.