The invention relates to the technical field of battery metal shells, and discloses an anti-loosening battery fixing device for a new energy automobile, the anti-loosening battery fixing device comprises an alloy plate, the inner side wall of the alloy plate is connected with a baffle in a penetrating manner, the side end of the baffle is connected with an arc-shaped cover in a penetrating manner, and the inner side wall of the arc-shaped cover is connected with a spherical shell mechanism in a penetrating manner; the interior of the spherical shell mechanism comprises a supporting shell, a movable ball, a folding frame, a supporting pad and a movable cover, and the outer side end of the folding frame is connected to the inner side wall of the supporting pad in a penetrating mode. The top end of the baffle plate is arc-shaped, so that the battery can be easily taken out, the risk of electric leakage caused by directly pulling the battery and even damage to the surface of the battery are avoided, the battery is not easy to fall off during installation, the compression spring scrapes the butt joint shell, the bottom side of the compression spring and the interface of the side wall of the butt joint shell are broken by grinding, the distance between the inner side walls of the alloy plate is shortened, and the service life of the battery is prolonged. The gap between the outer side walls of the battery is enlarged, so that the battery can be taken out conveniently, and the situation that the battery is deeper and difficult to take out is avoided.