The invention provides a packaging structure of packing barrels. Through the adoption of the packaging structure, the packing barrels can be conveniently stacked in the vertical direction, whether the packing barrels are unsealed or not can be quickly judged, and later dispute is prevented. The packaging structure comprises a first barrel body and a metal cover mounted on the upper end face of the first barrel body in a covering manner, and is characterized by further comprising a plastic ring, wherein the plastic ring comprises an upper positioning bulge, an inner wall packaging annular surface and a lower positioning structure; the inner wall packaging annular surface surrounds the connection part of the first barrel body and the covering annular surface of the metal cover; the upper positioning bulge is used for fixing the bottom of a second barrel body positioned at the upper part of the first barrel body; the lower end face of the upper positioning bulge tightly presses the upper end face of the outer edge of the metal cover; the upper end of the lower positioning structure is mounted on the lower end face of an outer edge curled edge of the first barrel body in a propped manner; a cavity composed of the outer edge curled edge of the first barrel body, an outer side curled edge of the metal cover and the inner wall packaging annular surface is filled with a sizing material structure; and the sizing material structure is used for sealing.