The invention discloses a pressure gauge shell wiring device which comprises a shell and a wiring case, wherein the shell is a hollow cylinder; the wiring case comprises a wiring head and a wiring cover; the wiring cover has a wire guide hole used for being penetrated by a wire; the wiring head comprises two parts, namely an upper wiring head and a lower wiring head; the lower wiring head includes a connecting area and a fixing area; the fixing area has a plurality of fixed through holes used for being penetrated by screws to be fixed with a gauge shell; the connecting area is provided with a plurality of lower wiring terminals; the upper wiring head is provided with a plurality of upper wiring terminals which correspond to the lower wiring terminals one by one and are matched with the lower wiring terminals in a splicing way, and the upper wiring head is clamped with the inner wall of the wiring cover; a long screw extends into the wiring cover from a screw hole and penetrates through the upper wiring head to be in threaded connection with the lower wiring head. When the pressure gauge shell wiring device is in use, only the wiring cover part which comprises the upper wiring head and the shell part which comprises the lower wiring head need to be spliced, and great convenience is also achieved when the maintenance and the replacement are needed due to a fault.