Provided is a batch-type substrate processing apparatus. The substrate processing apparatus includes a vertical reaction tube having an internal space for receiving a substrate boat in which a substrate is stacked in multiple stages, a deposition gas supply unit configured to supply a deposition gas inside the reaction tube, a heater disposed outside the reaction tube to provide a thermal energy inside the reaction tube, and an adhesion layer coated on an inner wall of the reaction tube and to which a deposition by-product layer by an excess deposition gas is attached.