The invention relates to the technical field of thick-wall container welding machining equipment, and discloses a welding robot supporting high frequency electric furnace preheating device for thick-wall container welding. The welding robot supporting high frequency electric furnace preheating device for thick-wall container welding comprises welding working end, a working end guide rail, a working end driving device, a high frequency coil group, a weld electric bridge and a shielding case, the working end guide rail is installed in a reel plate welding part accommodating cavity and parallel to a reel plate welding part in the axial direction, the welding working end is located in the reel plate welding part accommodating cavity and installed on the working end guide rail, and the workingend driving device is installed on one side of the welding working end; and the high frequency coil group is installed outside the reel plate welding part in a wound mode, the shielding case is in a flexible cylinder shape, and sleeves the working end guide rail and the welding working end. The invention provides equipment which uses a principle of a high frequency electric furnace to replace an acetylene flame burning welding part to realize the preheating of a thick-wall welding part, the adverse influence of acetylene flame burning on the weld quality can completely eliminated, meanwhile, an electromagnetic shielding device can realize the thermal shielding of a welding robot device and improve the process quality of a welding robot in the field.