A substrate processing apparatus includes a vacuum chamber including a top plate, a rotary table rotatably disposed in the vacuum chamber, a first process gas supply part that supplies a first process gas to be adsorbed on a surface of a substrate placed on the rotary table, a plasma processing gas supply part that is disposed apart from the first process gas supply part in a circumferential direction of the rotary table and supplies a second process gas to the surface of the substrate, a separation gas supply part that supplies a separation gas for separating the first process gas and the second process gas, a plasma generator that converts the second process gas into plasma, and an elevating mechanism that moves at least one of the plasma generator and the rotary table upward and downward.