While a rotational die and a predetermined position of a lower mold in which the rotational die is provided can be set in a zero contact manner, operation of setting the rotational die in the predetermined position of the lower mold can be easily performed, and occurrence of problems such as insufficient rotation of the rotational die and breakage of support shafts is reduced. To realize this, in a structure of bearing for rotatably supporting, in a bearing hole, a pivot support shaft of a rotational die arranged in a press molding apparatus, an inner diameter of at least an upper side of the bearing hole with respect to a horizontal line passing through a center of the bearing hole is formed slightly larger than a diameter of the support shaft, and a space is provided between the pivot support shaft and the inner surface of the upper side of the bearing hole.