Soil salinization is a major obstacle to the optimal utilization of land resources. Salt鄄affected soils are widely distributed throughout the world. The present extent of salt鄄affected soils substantially restricts plant growth in these areas. It has been demonstrated that leaching with water, chemical amendment, surface mulching with straw and phytoremediation are the most often used approaches to ameliorate saline soils. Engineering measures are also an effective solution to control salt movement in the saline soil. Establishing salt鄄isolation interlayers beneath the surface of saline soil is one of the most widely used engineering measures. Even though there are many studies dealing with salt鄄isolation interlayers establishment, very little is known about their effects on saline soil. Here, we used three salt鄄isolation materials to restrict the water and http: / / www.ecologica.cn salt movements in saline soil: zeolite, ceramsite and river sand. The aim of this study was to assess the effects of salt鄄 isolation interlayers application on soil water and salt movements in saline soil and on the photosynthetic characteristics of Robinia pseudoacacia in the coastal regions of Tianjin city. We also anticipate that the outcome of the study could form part of the basis for selection of salt鄄isolation materials in improving coastal saline soil with consideration of their costs. The