Abstract: The effect of the operating parameters on the ozonation of phenol aqueous solution in the presence of activated carbon fiber （ACF） was studied. The results showed that ACF could improve the ozonation significantly；the phenol removal at 10 min was 96.8% for 1g ACF，but only 68% for 1g GAC. The efficiencies of the process under acidic conditions were almost the same and higher than those under basic conditions；the increase of basic pH led to the decrease of phenol removal at the initial stage of the ozonation. The efficiency of ACF ozonation was improved by 17% at 10min when the ozonized-air flow rate increased from 0.04m3/h to 0.16m3/h. The increase of initial concentration from 100mg/L to 500mg/L only caused the decrease of phenol removal by less than 10%，but the total phenol removal increased significantly. The repeated use of ACF showed that ozonation could provide in situ ACF regeneration，which was considered highly beneficial in the industrial treatment process.