A housing is disclosed, including an accommodating cavity, where a surface of the housing is provided with a groove, a thickness of an area provided with the groove in the housing is less than a thickness of an area provided with no groove in the housing, the housing further includes a protective layer, and the protective layer is disposed on the surface of the housing and covers an opening end of the groove. The groove helps discharge a pressure from the housing, and the protective layer can prevent the housing from being accidentally broken. This application further provides a battery to which the housing is applied, and an electronic apparatus to which the battery is applied.