Abstract: A door assembly for mounting a lateral edge portion of a vehicle body, includes a door panel, a shield cover, a mounting rack, a flexible bulletproof sheet, and at least two stiff rods. The door panel includes an interior wall which has front and rear sides along a longitudinal direction. The shield cover is disposed to be spaced apart from the interior wall to define an elongate accommodation chamber therebetween which extends from the front side to the rear side. The mounting rack is detachably mounted on, and extends along the front side of the interior wall. The mounting rack has at least two lugs that extend in a transverse direction relative to the longitudinal direction. The lugs each define a mounting hole which faces towards the rear side of the interior wall. The flexible bulletproof sheet is disposed in the accommodating chamber and is of such a dimension as to overlay the shield cover. The flexible bulletproof sheet has left and right side portions along the longitudinal direction.