Providing an overturn preventing device which can maintain a mounted state against earthquake or the like with multidirectional shaking and thereby can prevent an article from overturn. The overturn preventing device includes a damper and a pair of bases. The damper is mounted between a top surface of a piece of furniture installed on a floor and a ceiling. Both ends of the damper are respectively coupled to the bases so as to be rotatable about respective rotation axes. Furthermore, both ends of the damper are respectively coupled to the bases so as to be swingable in a direction intersecting a rotation direction. The first base abuts against the top surface of the furniture and the second base abuts against the ceiling.