Packaging box capable of automatically locking bottom

The utility model relates to a packaging box capable of automatically locking the bottom, which comprises a box body, wherein the bottom of the box body is provided with two bottom covers and two folding wings, the two bottom covers are respectively arranged on the two opposite bottom edges of the bottom, the folding wings are respectively arranged on the other two opposite bottom edges of the bottom, the folding wings are triangular, and the bottom edges of the triangular folding wings are connected with the bottom edges of the bottom. The packaging box provided by the utility model can be automatically locked with the bottom covers by the triangular folding wings, and the folding wings can be folded outwards so as to reduce the thickness of the bottom and the volume of the folded packaging box, which is suitable for the stacking and packaging of the packaging boxes.