Waste gas detection box module convenient to maintain and waste gas detection device

The invention discloses a waste gas detection box module convenient to maintain and a waste gas monitoring device. The waste gas detection box module comprises a detection box body, a gas inlet mechanism, a heating and cooling mechanism and a waste gas concentration detector, a partition plate divides an inner cavity of the detection box body into an upper cavity and a lower cavity, the detection box body is provided with a maintenance box opening covering the upper cavity and the lower cavity, the maintenance box opening is sequentially covered with a plurality of strip-shaped sealing plates from top to bottom, the two edges of each sealing plate are in sliding connection with two sliding rail grooves respectively, vent holes are formed in the partition plate, an air outlet is formed in the side wall of the upper cavity, and an air inlet is formed in the side wall of the lower cavity; the gas inlet mechanism comprises a corrugated pipe spirally arranged in the upper cavity, and the two ends of the corrugated