A substrate processing apparatus includes: a processing container; an injector provided inside the processing container and having a shape extending in a longitudinal direction along which a processing gas is supplied; a holder fixed to the injector; a first magnet fixed to the holder and disposed inside the processing container; a second magnet separated from the first magnet by a partition plate and disposed outside the processing container; and a driving part configured to rotate the second magnet, wherein the first magnet and the second magnet are magnetically coupled to each other, and wherein by rotating the second magnet by the driving part, the first magnet magnetically coupled to the second magnet is rotated, and the injector rotates about the longitudinal direction as an axis.