The invention discloses a working environment detection system. The system comprises a smoke signal collection signal, a feedback calibration circuit and an operational amplifier output circuit; the smoke signal collection circuit adopts a smoke signal collector J1 in the model of LB-70C to collect a plant working environment smoke signal; the feedback calibration circuit is divided into two pathsto receive output signals of the smoke signal collection circuit; in one path, a composite circuit is composed of an inductor L1, a resistor R5 and a capacitor C3 so as to filter high-frequency noisein the signal, and a peak detection circuit is composed of an operational amplifier AR2, the operational amplifier AR4 and a diode D3 and the diode D4 to regulate signal peak value; in the second path, a delay circuit is composed of a triode Q1, a resistor R6 and a capacitor C2 to delay the signal, and the operational amplifier output circuit amplifies the signal through an in-phase manner by applying the operational amplifier AR7, and a pai type filter circuit is composed of the inductor L2, the capacitor C7 and the capacitor C8 to filter and output the signal; the smoke status in the working environment of the plant can be monitored in real time, the signal transmission stability is improved at the same time, and the signal frequency hopping and distortion are prevented.