Provided is a secondary battery, which can prevent explosion and fire of the battery by melting a safety film formed on an electrode tab to quickly clear a sealed state of a case when the internal temperature or pressure of the battery rises. The secondary battery includes an electrode assembly including a first electrode tab and a second electrode tab, and a case accommodating the electrode assembly such that the electrode tab is exposed to the outside. At least one of the first and second electrode tabs has a recess formed lengthwise on at least one of top and bottom surfaces of the at least one of the first and second electrode tabs, and a safety film is positioned in the recess.