Single porous In2O3 nanosheets and In2O3/C nanosheet composite with double phases of c-In2O3 and rh-In2O3 were fabricated by a facile one-step solvothermal treatment of a mixture of d-fructose and In(NO3)3 using urea as a precipitating agent in water–ethanol mixed solution followed by calcination. The effect of solution on the fabrication of In2O3 nanosheets was investigated and a possible mechanism was proposed to explain the formation of nanosheets. In2O3/C nanosheet composite electrode exhibited a high lithium storage capacity of 869mAhg−1 after 100 cycles at 100mAg−1, excellent rate and long-term cycling performance. The superior electrochemical performance could be ascribed to the incorporation of carbon and the unique nanosheet architecture of the nanocomposite.