Underground water pollution detection device

The invention relates to the technical field of environmental protection, and provides an underground water pollution detection device. The device comprises a sensor interface circuit connected with amain control circuit, and the sensor interface circuit comprises a signal conversion circuit and an amplifying circuit which are connected in sequence, wherein the input end of the signal conversioncircuit is used for being connected with a water quality detection sensor; the output end of the amplifying circuit is connected with the main control circuit, the signal conversion circuit comprisesa resistor R41, an operational amplifier U5A, an operational amplifier U5B and an operational amplifier U4A, one end of the resistor R41 is connected with the current output end IN1 of the water quality detection sensor, the other end of the resistor R41 is connected with the current output end IN2 of the water quality detection sensor, and one end of the resistor R41 is further connected with theoperational amplifier U5A;