Novelty Cu2O multi-branched nanowires and nanoparticles with size ranging from [Formula: see text]15[Formula: see text]nm to [Formula: see text]60[Formula: see text]nm have been synthesized by one-step hydrothermal process. These Cu2O nanostructures when used as anode materials for lithium-ion batteries exhibit the excellent electrochemical cycling stability and reduced polarization during the repeated charge/discharge process. The specific capacity of the Cu2O nanoparticles, multi-branched nanowires and microscale are maintained at 201.2[Formula: see text]mAh/g, 259.6[Formula: see text]mAh/g and 127.4[Formula: see text]mAh/g, respectively, under the current density of 0.1[Formula: see text]A/g after 50 cycles. The enhanced electrochemical performance of the Cu2O nanostructures compared with microscale counterpart can be attributed to the larger contact area between active Cu2O nanostructures/electrolyte interface, shorter diffusion length of Li[Formula: see text] within nanostructures and the improved stress release upon lithiation/delithiation.