Waste water discharged from Guangzhou Branch of China Petrochemical Corporation Limited has high concentration of ammonium and low COD/NH₄-N ratio.The waste water is treated by oxidation ditches and the removal efficiency of ammonium nitrogen is unstable. A zeolite percolator bed (ZPB) was developed and used to uptake and remove the ammonium nitrogen, organic compound, turbidity, etc. The oil refinery wastewater after treated by an oxidation ditch system and settlement process was fed to the ZPB continuously. The filtering velocity was 1 m·s^-1. The results showed that the ammonium nitrogen removal efficiency by ZPB was greater than 99% within the high effective period, and the averaged COD removal efficiency was about 24.8% by ZPB system. The removal of ammonium nitrogen and COD by using ZPB system was much better than those of activated charcoal bed (ACB) system and ceramisite particle bed (CPB) system.