To explore the feasibility of the coagulation-dissolved air flotation（DAF）-filtration process in the advanced wastewater treatment, a pilot study on the coagulation- dissolved air flotation-filtration advanced treatment process was carried out in a sewage treatment plant of Wuhan with the effluent from the secondary sedimentation tank of A2O process as raw water. The experiment completed the three factors and three levels orthogonal experiment of reflux ratio、dosage of coagulant、surface load three factors, COD、TP、turbidity removal rate as the evaluation index, the results showed that the dosage had the most significant effect on the removal of COD, total phosphorus and turbidity. The optimum operating parameters of the recommended process were surface load of 11.11m3/m2?h, dosage of 10mg/L and reflux ratio of 12%. Under this operating conditions, the unit water treatment power consumption and drug consumption for a total of 0.039yuan/m3; At the same time, the continuous flow test was carried out under the condition of fixed surface load of 10m3/m2?h. The results showed that under a certain water quality fluctuation condition, the process was reliable, the treatment effect was stable, the effluent COD concentration was stable below 15mg/L, The concentration is stable below 0.1mg/L, the turbidity of the effluent is less than 0.5 NTU, which has certain engineering application prospect.