The present invention provides a secondary battery which can restrain the break of an insulating film even though suffering the repeated change between the high temperature and the low temperature. The secondary battery 100 is equipped with an electrode body 80 on the outermost surface of which a clapboard 70 is arranged, a battery housing 30 and the insulating film 10 contacted with the electrode body 80 and the battery housing 30 to be kept. The thermal expansion coefficient of the battery housing may be lower than those of the insulating film and the clapboard. Portions of the insulating film, which are held in contact with the electrode body and the battery housing, may be adhered to the clapboard, which is positioned on the outermost surface of the electrode body, and the battery housing, respectively. A first 90 degree peeling strength of an adhesion portion between the insulating film and the battery housing is higher than a second 90 degree peeling strength of an adhesion portion between the insulating film and the clapboard. The first 90 degree peeling strength may be 15 mN/cm or higher, and the second 90 degree peeling strength may be 5 mN/cm or higher.