A gantry crane comprising a lightning protection device, wherein the lightning protection device comprises a conductive structure comprising a conductive wire , and the gantry crane has a rail , characterized in that , the lightning protection device further comprises: a rotatable rod structure, comprising a rotatable rod , wherein the rotatable rod is fitted inside an insulating sleeve at the top of the gantry crane ; an umbrella net structure , comprising a guide sleeve threadedly and rotatably connected with the rotatable rod in a sleeving manner, wherein the guide sleeve is arranged on an outer circumference of the rotatable rod , at least three conductive longitudinal rods are arranged at intervals in the circumferential direction of the guide sleeve , each of the conductive longitudinal rods has a curved radian, and at least two conductive cross-rings are arranged at intervals and around the conductive longitudinal rods ; the radii of the conductive cross-rings are different from each other so that the heights of positions of the conductive cross-rings are also different from each other when the umbrella net structure is unfolded; and the conductive structure further comprises a grounding carbon rod , wherein one end of the conductive wire is fixedly connected with a tail end of the rotatable rod , the other end thereof is connected with the grounding carbon rod , and in a lightning protection state, the conductive longitudinal rods extend out of the insulating sleeve , the conductive cross-rings unfold along the circumferential direction of the conductive longitudinal rods into an umbrella shape, and the conductive cross-rings and the conductive longitudinal rods together form an umbrella-shaped structure covering the upper part of the gantry crane , so that the gantry crane is shielded from lightning, wherein lightning is transmitted to the rotatable rod , and then transmitted to the conductive wire by the rotatable rod , and finally transmitted to the ground through the rail by the conductive wire via the grounding carbon rod . a rotatable rod structure, comprising a rotatable rod , wherein the rotatable rod is fitted inside an insulating sleeve at the top of the gantry crane ; an umbrella net structure , comprising a guide sleeve threadedly and rotatably connected with the rotatable rod in a sleeving manner, wherein the guide sleeve is arranged on an outer circumference of the rotatable rod , at least three conductive longitudinal rods are arranged at intervals in the circumferential direction of the guide sleeve , each of the conductive longitudinal rods has a curved radian, and at least two conductive cross-rings are arranged at intervals and around the conductive longitudinal rods ; the radii of the conductive cross-rings are different from each other so that the heights of positions of the conductive cross-rings are also different from each other when the umbrella net structure is unfolded; and the conductive structure further comprises a grounding carbon rod , wherein one end of the conductive wire is fixedly connected with a tail end of the rotatable rod , the other end thereof is connected with the grounding carbon rod , and in a lightning protection state, the conductive longitudinal rods extend out of the insulating sleeve , the conductive cross-rings unfold along the circumferential direction of the conductive longitudinal rods into an umbrella shape, and the conductive cross-rings and the conductive longitudinal rods together form an umbrella-shaped structure covering the upper part of the gantry crane , so that the gantry crane is shielded from lightning, wherein lightning is transmitted to the rotatable rod , and then transmitted to the conductive wire by the rotatable rod , and finally transmitted to the ground through the rail by the conductive wire via the grounding carbon rod . <EOS>