A substrate processing apparatus using plasma capable of efficiently controlling the selectivity ratio of a silicon layer and an oxide layer is provided. The substrate processing apparatus comprises a first space disposed between an electrode and an ion blocker; a second space disposed between the ion blocker and a shower head; a processing space under the shower head for processing a substrate; a first supply hole for providing a first gas for generating plasma to the first space; a second supply hole for providing a second gas to be mixed with an effluent of the plasma to the second space; and a first coating layer formed on a first surface of the shower head facing the second space, not formed on a second surface of the shower head facing the processing space, and containing nickel.