A combination process of Fenton-like and catalytic Mn (II) oxidation via molecular oxygen-induced abio-oxidation of As (III) -Mn (II) -rich acid mine drainage (AMD) is developed to rapidly and efficiently remove As and obtain low As-leaching solids in this study . The effect of pH, temperature, oxygen flow rate and neutralization reagent on As removal was investigated . The results showed that pH was important to As removal efficiency, which achieved maximum in 0.25-2 h, but decreased from ∼100% to ∼92.6% with the increase of pH 5-9. pH, temperature and oxygen flow rate played key roles in As (III) oxidation . The increase of As (III) oxidized from 16.8 to 67.1% to 98.6-99.0% occurred as increasing the pH 5-9 , 25-95 °C and oxygen flow rate of 0-2.4 L min . NaOH or Ca (OH) as base was less important to As removal . The mechanism involved Fenton-like reaction between Fe (II) and O for produced Fe (III) (oxy) hydroxide association with As (III + V) and Mn (II), catalytic Mn (II) oxidation for the formation of Mn (III, IV) oxides, and further As (III) oxidation by Mn (III, IV) oxides . As-bearing six-line ferrihydrite was the main solid product for low As-leaching fixation . pH 8 , 95 °C and oxygen flow rate of 1.6 L min were optimal for As removal.