Ethmo-maxillary bone buttress (EMBB) is a special complex bone structure in the interface between the internal wall and inferior wall of the orbit, which plays a vital role in maintaining the stability of the orbit, ethmoidal sinus and maxillary sinus.Although the incidence of compound fractures in orbital blowout fractures is lower than that of single orbital wall fractures, they have more obvious clinical symptoms such as enophthalmia and binocular diplopia.The mechanism of EMBB may be more supportive of the orbital floor compression theory, that is, the external force will lead to torn periostum and bone seam separation at the ethmoidomaxillary suture, and the orbital contents will form a funnel-like hernia due to extrusion and gravity.Or the extrusion results in the fracture and displacement of the orbital lamina of ethmoid bone, the upper wall of the maxilla and the ethmoidomaxillary plate, causing a large area of orbital wall collapse and obvious expansion of the orbital cavity.Recently, the study of orbital internal wall and inferior wall joint fracture has become a new hotspot, but research on the orbital blowout fracture involving ethmo-maxillary bone buttress is still in its infancy.The current orbital fracture repair technique can only restore the connection between the two orbital walls, and there is no surgical plan can overall recover EMBB's scaffolds role.Therefore, how to restore the scaffolds role of EMBB, and to regain the part of ostiomeatal complex in normal sinus drainage is the challenge we need to conquer.In this article, the anatomy and clinical characteristics of the supporting structure, fracture mechanism, and the research progress and prospect of surgical repair technique were reviewed.