The present invention provides a packaging box and stop wall of packaging box. The packaging box includes at least bottom plate, four third box-body splicing elements and four stop walls. The third box-body splicing element is fixed at each corner of the bottom plate and the two ends of stop wall are connected respectively to the two third box-body splicing elements on a side of the bottom plate and fixed between the two third box-body splicing elements to form with the bottom plate a semi-closed packaging box having open top. As such, the present invention can realize the packaging of liquid crystal panels of different sizes and increase the utilization efficiency of the packaging box to protect the liquid crystal panels as well as reducing packaging cost.