The invention provides a monitoring system of an electromagnetic environment of vehicle-mounted train control equipment for a train. The monitoring system comprises a control unit (1), a switching unit (2), a sensor unit (3) and an instrument unit (4), wherein the sensor unit (3) comprises at least one sensor for sensing an alternating current, at least one sensor for sensing an alternating electric field and at least one sensor for sending an alternating magnetic field; the sensors are respectively used for sensing the alternating current, the alternating electric field and the alternating magnetic field to generate multiple radio frequency electrical signals; the control unit (1) is used for sending a control signal to the switching unit (2); the switching unit (2) is used for responding the control signal from the control unit (1) to output at least one of the multiple radio frequency electric signals from the sensor unit (3) to the instrument unit (4); and the instrument unit (4) is used for carrying out frequency spectrum analysis or time domain envelope analysis on the radio frequency electric signals from the switching unit (2) and feeding back measurement data to the control unit (1).