Introduction.Lithium-ion battery is one of high capacitance rechargeable batteries,and its applications are expanded to electric automobiles and aircrafts.Because of the high energy density,the reliability of the battery should be established to prevent serious incidents.Especially,various loads such as static load,impact load and cyclic load are applied on the constituent members in the automobiles and the aircrafts.This study has investigated the mechanical property of the electrode in the lithium-ion battery.The tensile test was performed by using the negative electrode which consisted of the carbon film as the active material pasted on the copper foil.