Abstract: The studies about the effects of components added to such soil and the interactions between each of components on plant growth and the erosion against rain of such synthetic soils were very important. Inorder to improve the water status of the special synthetic soils used on the hydroseeding technique, keepiing-and-absorbing water properties as well as the effects of water absorbent polymer on soil physical properties were performed. Based on the results, the maximum absorbing content of water absorbent polymer reached to 500 times, and when water absorbent polymer was added into soils, the soil water status was significantly improved (p<0.05), and the time of its keeping water could maintain 12h and 8h treated with 30° and 50°, respectively. Forthemore, siol bulk density, specific gravity decreased and total porosity increased with the increase of water absorbent polymer content.