Abstract: The regulation of water quality in aquaculture ponds that controlling factors of aquaculture,is also an inevitable requirement for achieving high-quality development of fishery.According to the problems on water quality of intensive tilapia culture systems in the northwest inland,China,this research aimed to examine the water quality impact of aquaponics system.We constructed an Oreochroms mossambcus-Ipomoea aquatica symbiosis system in Midong County,Urumqi.This system used floating bed for removing nitrogen and phosphorus,while each floating bed area was 4.32 m² (360 cm×120 cm).This research used floating bed 96,about 415 m²,which account for 8.3% of tilapia culture pond area.The research time was 126 days(May 18 ~September 20,2017).The results were showed as compared with the control group,the Oreochroms mossambcus-Ipomoea aquatica symbiosis system significantly decreased the pH,total phosphorus(TP) and nitrate nitrogen(NO₃^--N) in aquaculture ponds(P<0.05),the content of total nitrogen(TN),ammonia nitrogen(NH₄⁺-N),and nitrite nitrogen(NO₂^--N) showed an increasing tendency to decline than control group with significant differences(P<0.05).Symbiosis system could increase the utilization of nitrogen and phosphorus by 13.5% and 6.4%,significantly decrease pollutants discharge coefficient(P<0.05) and increase discharge standard of aquaculture wastewater,that had no effect on fish growth.Therefore,aquaponics system can be used to control the water quality of ponds in the northwest China.