Si-based alloy powders were studied as anode material for Li-ion battery (LIB). The Si-based alloy powders were manufactured by mechanical ball milling process. The ball milled Si-based alloy powders were incorporated graphite as a bufferring matrix to depress the volumetric change of an alloy electrode. We investigated structural and electorchemical properties of the Si-based alloy anodes. Consequently, we obtained good results having an excellent coloumbic efficiency of 85%. Also, we found not only a large initial capacity of 620mAh/g but also a high capacity retention of 90% at the 100th cycle.