A door having a reference hole (11), a second hole (12), a third hole (13) and a fourth hole (14), and a method of manufacturing the same. Common location pins are fitted into the respective holes (11, 12, 13, 14) to position an inner panel (2), a hinge panel (3) and a belt-like reinforcement member (4), which constitute an inner panel assembly (5), relative to one another in all directions including a longitudinal direction, vertical direction, lateral direction and a direction of rotation, to position the inner panel assembly (5) and an outer panel (6) relative to each other, and to position component parts of a door panel relative to one another to complete the door panel, and equipment parts being mounted in association with the respective component parts are equipped. Thus a stable door is ensured with less labor and fewer positioning members.