Providing an overturn preventing device which can successfully prevent overturn of an article. The overturn preventing device includes a damper mounted between a piece of furniture and a ceiling and a setting member connected to both ends of the damper. The setting member has a first setting part body and a second setting part body. The first and second setting part bodies and of the setting member are spread when the overturn preventing device is mounted between the furniture and the ceiling. The setting member assumes such a shape as to extend in one direction when the first and second setting part bodies and are unspread.