The invention discloses an automobile rear apron structure which comprises a rear apron inner plate, a rear apron outer plate and a rear apron beam. The rear apron inner plate and the rear apron outer plate are connected in a welded mode and form a first sealed cavity. The lower rim of the rear apron beam is connected with the rear apron inner plate in a welded mode. The upper rim of the rear apron beam is connected with the rear apron outer plate in a welded mode, so that the rear apron beam, the rear apron inner plate and the rear apron outer plate form a second sealed cavity. The first sealed cavity is located above the second sealed cavity. Compared with a traditional automobile rear apron structure, the area of the section of the cavity structures is improved and the bending rigidity and the torsion rigidity of a rear apron on the rear of a finished automobile are improved. Meanwhile, the rigidity and the strength of the rear apron beam cavity structure are boosted, so that in the process of rear-end collision of the finished automobile, the rear apron beam can fully absorb the collision energy, risks of fuel leakage caused by collision and damage of a fuel tank are avoided and safety of the finished automobile is improved.