To avoid damage on fresh fruits or the like stored in a packaging container 15 and stably and surely support the fresh fruit packaging container by alleviating an external force applied to the bottom part of the packaging container 15 through a bottom panel 1 of a tray-shaped packaging box.

The tray-shaped packaging box is formed by erecting panels forming side walls of the box from two opposing sides of the bottom panel 1, erecting panels forming end walls of the box from the other two opposing sides of the bottom panel 1 and fixing the panels of these adjoining side walls and the panels of the end walls to each other to form the box having its upper surface opened. Part of the inner wall of the box is expanded inside the box as pack supporting panels 11, 11. The package container 15 stored in the box is supported by the pack supporting panels 11, 11. Part of the inner wall of the box connected with the pack supporting panels 11, 11 is erected from the bottom panel 1 of the box and arranged at the side part of the box as auxiliary flaps 21, 21 supporting the pack supporting panels 11, 11.