The invention discloses an extravascular protection support which comprises a roll booster, a hollow protection tube and a hollow separator. The roll booster, the hollow protection tube and the hollow separator are sequentially arranged, a protection gap which is parallel to the central axis of the protection tube and penetrates through the two ends of the protection tube is formed in the side wall of the protection tube, a separation gap penetrating through the two ends of the separator is formed in the side wall of the separator, and the protection gap and the separation gap are centrally and linearly arranged. The separator and the protection tube are arranged, when the support is used, after the arteria carotis communis bifureation is separated through the submandibular incision, the internal carotid is exposed out, the internal carotid is sequentially wrapped by the separator and the protection tube, the separation gap and the protection gap are towards the outer side, the closed walls are towards the inner side, and exactly face the surgical operation direction, surgeons can fully and boldly remove diseased tissue in the operation, the accident that the internal carotid is accidentally injured, and the massive haemorrhage happens can be avoided, and the surgical treatment is improved.