The invention relates to a switch cabinet, a three-position isolation switching mechanism and a mistake switching prevention grounding interlocking device of the three-position isolation switching mechanism. The mistake switching prevention grounding interlocking device of the three-position isolation switching mechanism comprises a rack and a mistake switching prevention grounding linkage mechanism, wherein the mistake switching prevention grounding linkage mechanism comprises a linkage rotation element and a linkage element, the linkage rotation element is used for synchronously rotating with a worm gear of the three-position isolation switching mechanism, the linkage element is connected with the rack and comprises a grounding locking element, a locking structure is arranged on the linkage rotation element and can be locked by the grounding locking element when the three-position isolation switching mechanism is at a grounding position, the linkage element is connected with a driving device, and the driving device can be used for driving the grounding locking element to lock the locking structure and limit the linkage rotation element to rotate when the three-position isolation switching mechanism is at the grounding position. By the mistake switching prevention grounding interlocking device, the problem that mistake switching grounding operation of the three-position isolation switching mechanism cannot be forcedly prevented is solved.