Abstract: A method for predicting a discharge level of an effluent from decentralized sewage treatment facilities, the method including: measuring the conductivity of an influent, the conductivity and suspended solids concentration of an effluent of a plurality of decentralized sewage treatment facilities; repeatedly measuring a pH, a concentration of COD, a concentration of ammonia nitrogen, the concentration of total phosphorus of the effluent of each of the plurality of decentralized sewage treatment facilities; calculating average values of the pH, the concentration of COD, the concentration of ammonia nitrogen, the concentration of total phosphorus; comparing the average values with a local sewage discharge standard, and determining a discharge level of the effluent; constructing a predictive model; and sampling an influent and an effluent of a sewage treatment facility, measuring the conductivity of an influent, the conductivity and suspended solids concentration of the effluent, inputting the obtained data to th