The invention discloses a sewage treatment detection method which is characterized by comprising the following steps: step 1, adopting a sewage treatment detection device, putting a detection frame plate of the device into a detection sewage pool, and adjusting and controlling the detection height through a moving assembly according to actual conditions; step 2, after positioning, controlling a traction rope, obtaining the water quality condition of the pool bottom through a second water quality sensor, and sending the information to a central processor for analysis and processing; 3, when sewage at the top of the sewage pool is detected, a homogenizing assembly is started to suck the sewage at the bottom of the device into the device, the sewage is stirred and then enters a U-shaped channel, at the moment, four first water quality sensors obtain the water quality condition of the homogenized sewage, meanwhile, the sewage in the U-shaped channel can be squeezed out, sewage detection and resampling are achieved, and the detection accuracy is improved. Sending the two groups of detection signals to a central processor for analysis and processing, and taking a mean value of simultaneous detection; and step 4, processing the three groups of numerical values, and sending the processed numerical values to a remote control terminal for display through a signal transmitter.