The invention provides an M-shaped electromagnetic signal emitting pin for power transmission wire insulators. A cross beam realizes the mutual connection with upper insulator and lower insulator group pairs and suspends a power transmission wire, a pin is arranged in a middle hole of the upper insulator, the upper part of the lower insulator is provided with a connecting post provided with a connecting hole, a pin hole is formed in the wall of the connecting hole, and the pin is inserted in the pin hole. A structure of the pin is in an M shape, and an electromagnetic signal emitter is arranged on the pin. An electromagnetic sensing power generator provided with a sensing coil is suspended between the power transmission wire and the insulator positioned at the lowermost part through an insulation hook, one end of the sensing coil is connected with a grounding wire, the other end of the sensing coil is used as a power supply output wire, and the power supply output wire is respectively connected with a pin circuit inserted between the insulator group pairs. A signal receiving display corresponding to each group of insulator pins is arranged on a handheld remote measuring device. The M-shaped electromagnetic signal emitting pin for the power transmission wire insulators has the advantage that the position state of the pin can be monitored in real time. The M-shaped electromagnetic signal emitting pin is suitable for being used as a power transmission wire insulator pin monitoring device.