A substrate processing apparatus includes a chamber, a susceptor provided in the chamber, a shower plate having a plate part provided with a plurality of through holes and formed of a conductor, a ring-shaped part connected to an outer edge of the plate part, surrounding the plate part and formed of a conductor and a lead wire embedded in the ring-shaped part and surrounding the plate part and the susceptor in plan view, the shower plate being provided so as to face the susceptor in the chamber, and a DC power supply that supplies a direct current to the lead wire.