Abstract:The use of sewage effluent subjected to proper treatment for agricultural irrigation has been increasingly considered as a supplemental source of freshwater in many countries where a shortage of potable water is current reality. However, concern exists over the pollution risk due to the toxic accumulation from sewage effluent, which is the main restraint on the application of sewage effluent irrigation. Extensive researches on system stability, environmental sustainability, and efficient control are highly necessary to ensure the efficient and safe use of sewage effluent for agricultural irrigation. The effects of sewage effluent application on drip emitters, irrigation system, environments and agricultural products were reviewed. The behaviors and interaction between nutrients, salts, microorganisms and typical pollutants were summarized. Several theoretical and technical issues that need to be further studied, including the micro mechanism and macro behaviors of the influences of sewage application on irrigation system performance, the dynamics process of environmental changes imposed by sewage irrigation, the effects of sewage application on nutrient uptake and utilization, and efficiently safe control mechanisms of sewage irrigation, were prospected. Expected researches on these issues can add new knowledge to the regulation theory of water, nutrients and salts for irrigation and it will be a contribution to enhancing the efficiency and safty of use of sewage effluent for agricultural irrigation.