In order to avoid the pollution of dairy product processing wastewater and the waste of online water quality monitoring data, a research on the regulation technology of dairy product processing wastewater treatment based on the online monitoring data of effluent water quality was carried out. This experiment is based on a UASB-A/O treatment process pilot scale of a dairy processing wastewater treatment station, and the relevant kinetic parameters are measured to determine the correlation between the effluent water quality indicators and process operating parameters such as sludge load and sludge age. Use this relationship to guide the process parameter adjustment and improve the effluent water quality. The research results show that there is a good correlation between effluent Se and external operating parameters such as sludge load, sludge age and DO, and the optimal control range of sludge load is 0.0766∼0.0998 kgBOD/(kgMLSS·d); The optimal control range of sludge age is 33∼38 d.And when the sludge concentration (MLSS) changes between 2800∼3500 mg/L, the effluent water quality is better. According to the obtained process control method, the pilot plant is adjusted accordingly, and the effect is significant. Water quality indicators such as effluent Se and ammonia nitrogen change significantly, and the effect of nitrogen and phosphorus removal becomes better, which meets the needs of practical engineering.