Tin and tin-aluminum thin film anodes for lithium ion battery are deposited on a copper substrate by radio frequency (RF)-magnetron sputtering at room temperature. Charge/discharge characteristics are compared. It is indicateds that tin-aluminum anode has higher capacity and better cycle performance than that of pure tin anode. XRD shows that tThe tin-aluminum thin film is a mischcrystal alloy. The first discharge capacities of tin and tin-aluminum are 750mAh/g and 1205mAh/g respectively. After 30 times charge/discharge, the specific capacity of tin-aluminum anode is 780mAh/g. , compared with 530mAh/g for pure tin anode. From above results, tThe mischcrystal alloying tin with aluminum has effectively improved the electrochemical performance of tin anode. The tin-aluminum mischcrystal alloy will be a promising anode material for lithium ion battery.