Abstract: In arid and semiarid climatic areas, water shortage is a dominant factor for low harvest in rainfed farming. Application of polyacrylamide(PAM) on the soil surface can significantly increase water infiltration of soils. A field experiment was conducted at Qingshuihe, near Huhhot, Inner Mongolia. The experimental site, with slope of 5% to 7%, consisted of 12 nearby rectangle plots, of about 10 by 16 m. The experiments applied four soil surface treatments (one control and three PAM coverage rates: 80%, 60%, 40%). The experiments showed that PAM application reduced runoff and increased water penetration into soil significantly and corns planting in the soils treated with PAM were significantly taller and more vigorous.