The invention discloses a ground electromagnetic signal detecting circuit. The circuit comprises two impedance coupling circuits, two low pass filter circuits, a plurality of active filter circuits, two optional attenuation circuits, a differential amplification circuit, two optional gain circuits and an AD conversion circuit, wherein the two impedance coupling circuits are connected to an input interface and are used for coupling an input signal into a weak signal detection circuit; each low pass filter is connected to one impedance coupling circuit and is used for filtering the input signal;the plurality of active filter circuits are divided into two groups, each group includes the plurality of active filter circuits, each group of the active filter circuits is connected to one low passfilter circuit, the active filter circuits in each group are connected in parallel, and the plurality of active filter circuits are used for filtering signals output by low pass filters; the two optional attenuation circuits are used for adjusting the grounding resistance of the weak signal detection circuit; the differential amplification circuit is connected to the optional attenuation circuits; the two optional gain circuits are connected to the differential amplification circuit; and the AD conversion circuit is connected to the optional gain circuits. In the invention, a weak signal canbe accurately detected.