The invention relates to a high-pressure switch shell assembly and a manufacturing method of the high-pressure switch shell assembly. The high-pressure switch shell assembly comprises a main cylinder body with the axis stretching in the left-right direction. The upper end of the main cylinder is symmetrically provided with two upper support cylinder bodies for connecting corresponding current sensors and corresponding sleeves. The upper end of each upper support cylinder is provided with an upper support cylinder body flange. The high-pressure switch shell assembly further comprises support legs corresponding to the upper support cylinder bodies respectively. Each support leg is provided with a flange connection portion fixedly connected with the lower end face of the front side and the lower end of the rear side of the corresponding upper support cylinder body flange in a welding mode, a support cylinder body connection portion fixedly connected with the peripheral arc face of the front side and the peripheral arc face of the rear side of the corresponding upper support cylinder body in a welding mode, and a main cylinder body connection portion fixedly connected with the peripheral arc face of the front side and the peripheral arc face of the rear side of the main cylinder body in a welding mode. The upper support cylinder bodies of the high-pressure switch shell assembly are high in structure strength.