Experimental-theoretical substantiation of new plasma-chemical technologies for obtaining of extra pure silica and polycrystalline silicon has been realized. In optimal conditions, general coefficient of reducing of additives contents equals to ~2–4, while individual coefficients for Na, Fe, Ca, K attain to 5–10 and more points with obtaining of extra pure silica. Laboratory equipment for researching of efficiency of plasma-chemical method for obtaining of polycrystalline silicon has been developed. Previous experiments of plasma-chemical reduction of silicon from silica have been realized. Purity of obtained silicon is 92,2–99,8%.