Salinity of soil and water resources is one of the most important problems which reduce agricultural production and gradually decrease the area under cultivations. One of the effective methods of reducing the salinity hazard is the application of leaching and leaching management. In this study, the effect of three irrigation water qualities of 4, 9 and 12 dS/m and four leaching levels of 0, 17, 29 and 37 percent in a silty clay loam soil on wheat yield and some chemical characteristics of soil and drainage water was investigated. The study was carried out in a greenhouse at Isfahan University of Technology in completely randomized design as factorial with 7 replications. The results showed that soil salinity, sodium adsorption ratio and exchangeable sodium percent increase with increasing in salinity of irrigation water and increase as leaching level decreases and these values are greater for soil depth of 0-15 cm as compared to soil depth of 15-30 cm. The increase of leaching level increases soil acidity, and soil acidity in the lower layer was greater than the top layer, but the changes were not significant. With increase of quality and quantity of leaching water, the wheat grain and straw yield, stem and spike length, number of grains per spike, number of seedlings, percent of emergence, weight of 1000 grains and harvest index increase and lower Cl and Na concentrations of wheat decrease. As salinity of irrigation water increased, the salinity of drainage water increased and the volumes of irrigation and drainage water decreased. Application of leaching in the best and worst irrigation water qualities (salinity of 4 and 12 dS/m) had the most and worst leaching efficiency, respectively. The most saline drainage water and the most changes in salinities of drainage waters were belonged to the three first irrigations at the beginning of the season. In later irrigations the changes in drainage water decreased significantly and change process became nearly consonant.