Abstract: Membrane bioreactor(MBR) has been widely applied to the treatment of ship's oily wastewater. To study the operating parameters of MBR on the treatment of oily wastewater produced by onboard restaurants, wastewater is first produced from axunge which simulates the water characteristics of ship's oily wastewater, and a small shore-based MBR system is subsequently founded.Chemical Oxygen Demand(COD), Biochemical Oxygen Demand(BOD), ammonia nitrogen are tested with the measuring device like spectroscope.The relationship between the Hydraulic Retention Time(HRT) s, COD, BOD, ammonia nitrogen, membrane pressure and sludge concentration during the 70 days operation of the MBR system is also studied, which shows that the MBR could remove the COD, oil, TOC, BOD by over 80% and ammonia nitrogen by over 50% in oily wastewater.Furthermore, the research also indicates that the oil greatly affects the membrane fouling.