PROBLEM TO BE SOLVED: To provide a packing box of a small motor having a support body capable of surely holding even if an attached part is different, when the motor is the same.SOLUTION: A packing box of the present invention is composed of a box body 30 and a support body 10A, and is respectively folded up from one corrugated board. The support body 10A forms a square cylinder 10D which has an insertion piece 11 extended on both side ends and which has an upper surface downwardly inclining to the outside formed by successively respectively vertically bending parallel fold lines a-e toward the center from both sides, and the insertion piece 11 is penetrated through the outside of the square cylinder 10D from an insertion part 16a provided on a bottom plate 16, and is locked and assembled on an outside wall 15. A fitting hole 14a for inserting-fitting a motor case is provided in a plurality on an upper plate 14 of the square cylinder 10D, and a lower plate 12 is provided with a locking hole 12a for engaging a
