This study examines growth responses of Phragmites communis to controlled changes in the water table in the semiarid areas of the Horqin Sand Land. Water table level treatments were a natural control which the water table is deeper than 200 centimeters, 40 centimeters, 80 centimeters, 120 centimeters and 180 centimeters below the soil surface. We found that the water table between 0-200 centimeter was more advantageous for Phragmites to grow than natural control. And also we found significantly different growing characteristics of Phragmites communis with the different water table depths.The root-shoot ratio and the vertical root length increased gradually as the water table decreased from 40-120 cm,whereas the root-shoot ratio increased below a water table of 120 cm. The root density of the Phragmites communis was higher at water tables of 0-120cm than at water tables of 120-200 cm. At shallow water tables above 40cm depth, although rates of transpiration and photosynthesis of Phragmites communis was inhibited, however plant height, leaf area and biomass of the Phragmites communis at shallow water was higher than that at natural control.