Disclosed is an apparatus and method of processing substrate, which facilitates to improve deposition uniformity of a thin film deposited on a substrate, and to control quality of a thin film, wherein the apparatus includes a process chamber; a substrate supporter for supporting at least one of substrates, wherein the substrate supporter is provided in the bottom of the process chamber; a chamber lid confronting the substrate supporter, the chamber lid for covering an upper side of the process chamber; and a gas distributor for locally distributing activated source gas on the substrate, wherein the gas distributor locally confronting the substrate supporter is provided in the chamber lid, wherein the gas distributor forms plasma by the use of plasma formation gas, and activates the source gas by distributing the source gas to some of plasma area for formation of the plasma.