To clarify the effect of silicate application on the reduction of summer drought damage of orchardgrass, a pot experiment treated with 3 levels of available SiO$_2$ 100(control), 150, and 200 ppm was carried out in the phytotron, and field experiment in the medium textured hilly soils also was carried out. The plant height and weight of orchardgrass grown in the pots were increased with increasing of SiO$_2$ application, and the higher content of SiO$_2$ in plant became erect types of leaves with low ethylene evolution. With application of SiO$_2$ in the hilly soils, the reduction of summer drought phenomenon was recognized by the increasing 9% in yield with decreased ethylene evolution at summer drought stage but the nutritive values of the plant were not deteriorated.