The oxidative degradation of 4-chlorophenol (4-CP) in aqueous solution induced byplasma with submersed glow discharge has been investigated. The concentration of 4-CP andthe reaction intermediates were determined by high performance liquid chromatography (HPLC).Various influencing factors such as the initial pH, the concentration of 4-CP and the catalyticaction of Fe2+ were examined.The results indicate that 4-CP is eventually degraded into inorganic ion, dioxide carbon andwater. The attack of hydroxyl radicals on the benzene rings of 4-CP in the initial stage of oxidativereactions is presumed to be a key step. They also suggest that the reaction is of a pseudo-firstorder kinetic reaction and the proposed method is an efficient way for the 4-CP degradation. The concentration of 4-CP and the reaction intermediates were determined by high performance liquid chromatography (HPLC). Variety influencing factors such as the initial pH, the concentration of 4-CP and the catalytic activity of Fe2 + were examined. The results indicate that 4-CP was eventually degraded into inorganic ion, dioxide carbon and water. The attack of hydroxyl radicals on the benzene rings of 4-CP in the initial stage of oxidative reactions is presumed to be a key step. They also suggest that the reaction is a pseudo-firstorder kinetic reaction and the proposed method is an efficient way for the 4-CP degradation.