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In order to study hydraulic characteristics and their differences of SDI emitter in various textural soils and to analyze effect of soil factors on emitter discharge, the experimental scheme was arranged in the clay, loam and sand soil based on uniform design with mixed levels of three factors that were respectively work pressure of emitter, soil bulk density and soil initial water content. The results show that the rules of emitter discharges in three textural soils are the same. The discharge of SDI emitter is slightly big at the beginning of irrigation, but it is reduced and tends to be constant after 1～2min when work pressure remains invariable. At the same work pressure, the discharge of SDI emitter is smaller about 5～20 percent than that of DI emitter. The work pressure is higher, and the discharge of SDI emitter is bigger, and the discharge of both SDI and DI are closer. Soil factors slightly restrict emitter discharge. The lighter textured soil it is, the bigger emitter discharge will be. But discharge reduction of emitter in three textural soils with increase of soil bulk density or soil initial water content is bigger in sandy soil, smaller in loam soil and smallest in clay soil. 