Novel copper-antimony (Cu2Sb) alloy-nanoparticle clusters (CANCs) supported on porous Cu networks are successfully synthesized by electrodeposition. The porous structures in CANCs can provide adequate void space to accommodate volume change during charging/discharging, and accordingly can prevent the pulverization and electrical isolation, enabling long-term cycling. The porous Cu networks as supports can provide large surface areas for the growth of CANCs, excellent electron transportation for charge/discharge, and an efficient "buffer zone" for volume fluctuation of Cu2Sb alloys. The CANCs show superior electrochemical performance, such as high and reversible capacity and superior long-term cycle stability. With ease of large scale fabrication, low-cost, environmentally friendly, and superior electrochemical characteristics, the CANCs qualify as a promising candidate for anode materials of Li-ion batteries with high performance.