A hollowly cylindrical supporting body is used for an electrical stimulation probe, and the electrical stimulation probe provides an insulated outer shell. The insulated outer shell can accommodate and cover the hollowly cylindrical supporting body. Further, the hollowly cylindrical supporting body can be assembled precisely with the insulated outer shell through Fool-Proofing Design. Therefore, the insulated outer shell and the hollowly cylindrical supporting body can be combined closely and joined together to form the electrical stimulation probe of the present invention.
