The invention discloses a new energy automobile battery mounting device. A battery is fixedly arranged in a fixing frame, multiple elastic supporting feet are arranged between the undersurface of thebattery and the inner wall of the bottom of the fixing frame, an elastic piece component is arranged between the side face of the battery and the side wall of the fixing frame, an upper fixing cover plate is hinged on one side of the upper end face of the fixing frame by adopting a hinging shaft, a locking buckle component is arranged on the other side of the upper end face of the fixing frame, and a waterproof plate is fixedly arranged on the top face of the locking buckle component. The battery mounting device is simple and convenient; after a battery is arranged in the fixing frame, the battery can be fixed effectively by only closing a fastening plate and arranging a buckle on the fixing frame in a clamped manner, so that convenience is brought to cleaning the battery, and dust pollution is prevented; a radiator can conveniently radiate heat of the battery, and an elastic piece on the side wall can well buffer the battery; the elastic piece is of a bilayer structure, so that buffering effect can be improved, and the battery can be protected better.