Porous nanosheets-assembled Co3O4 microspheres have been first successfully fabricated by a facile solvothermal method without any surfactant followed by a relatively low annealing temperature (400°C) with a higher specific surface area compared to the annealing temperature of 600°C. The nanosheets-assembled microspheres exhibit a high discharge capacity of 1000mAhg−1 at a current density of 100mAg−1 after 50 cycles and 850mAhg−1 at a current density of 500mAg−1 after 80 cycles, even at a high current density of 1.6Ag−1 the cycling reversible capacity can still keep 750mAhg−1, the representative capacities are relatively higher than most of reports about pure Co3O4. We attribute the excellent electrochemical performances to the porous nanosheets structure and architectures, which can provide more effective electrode/electrolyte contact area and direct ion transmission path, then lead to faster lithium-ion diffusion, confirmed by EIS measurements. The high specific capacity, excellent cycling and rate performances demonstrate that the porous nanosheets assembled microspheres present promising application in lithium storage.