The organic waste alkali solution was treated through acid - base neutralization, flocculation precipitation and Fenton oxidation, and the influencing factors were systematically studied. The experimental results showed that the water quality was neutral when organic waste alkali liquor and waste acid were mixed with 500∶13; when the dosage of polyaluminium chloride ( PAC ) was 1.92 kg/t and the dosage of APAM was 0.01 kg/t, the removal rate of COD was 77.8%. After flocculation precipitation, Fenton oxidation reaction was carried out for three hours when organic waste alkali liquor and waste acid ware mixed with 500:2, and the dosages ferrous sulfate heptahydrate and 30% hydrogen peroxide were 16.68 kg/t and 200 L/t respectively, then calcium oxide and anionic polyacrylamide ( APAM ) were added for flocculation precipitation. When the dosage of calcium oxide was 14 kg/t, the dosage of APAM was 0.01 kg/t, COD of the effluent water was reduced to 2 724 mg/L, the removal rate of COD was 95.3%, sulfide was decreased to 0.006 mg/L, the removal rate of sulfide was 99.9%, BOD of the effluent water was decreased to 1 228.5 mg/L, B/C was 0.45, and it could enter the biochemical system.