A dry etching method includes: mounting a silicon substrate on an electrode arranged in a processing chamber; generating a plasma by discharging an etching gas in the processing chamber; supplying to the electrode a radio frequency power for attracting ions from the plasma; and etching the silicon substrate by the plasma by using an inorganic mask containing silicon as an etching mask. An absolute value of a self-bias voltage generated in the electrode is equal to or smaller than about 280 V, and wherein the etching is carried out while satisfying the following equation: y.ltoreq.0.0114x+0.171, where x is a pressure inside the processing chamber and y is a power density of the radio frequency power per unit area of the electrode.