The utility model provides an external pressure loading device of a bulb cone structure. The device comprises an upper end top cover, a conical cylinder segment, and a pressure air bag and an annular air bag sealing strip to seal the pressure air bag. The upper end top cover is provided with air inlet and outlet ports and first connecting holes distributed uniformly. The conical cylinder segment comprises an upper connecting ring, a cone inner wall cylinder connected with the upper connecting ring, a lower end ring connected with the cone inner wall cylinder, and a bottom cone annular cylinder connected with the lower end ring. The internal diameter of the bottom cone annular cylinder is lower than the internal diameter of the lower end ring. The upper connecting ring is provided with second connecting holes distributed uniformly. The annular air bag sealing strip is provided with third connecting holes distributed uniformly. The pressure air bag is disposed between the upper end top cover and the upper connecting ring. The pressure air bag is communicated with the air inlet and outlet ports. The main body of the air bag is attached to the inner wall of the conical cylinder segment. The device can effectively realize applying of uniform distributed external pressure load on the irregular cambered surface cylinder segment, and installation difficulty of the pressure device is effectively reduced, and installation period is shortened.