In the foregoing description about the structure and operation of the substrate processing apparatus 1, the substrates W held in the common carrier SC are transferred into the exclusive carrier in a horizontal attitude, and then turned into a vertical attitude together with the exclusive carrier. This allows a speedy and simple turn of the substrates W inside the apparatus. Further, such a simple mechanism of the apparatus suppresses generation of particles, thereby improving the substrates W in quality. Consequently, the substrate processing apparatus for processing substrates in a vertical attitude can be easily introduced into a substrate processing system which consists of a plurality of substrate processing apparatuses, even if the substrates are transferred in a horizontal attitude between the apparatuses. Furthermore, since the turning stage 231 turns around the horizontal axis 231C, the horizontal storage position H of the exclusive carrier EC at which the substrates W are held in a horizontal attitude, becomes adjacent to its vertical storage position S at which the substrates W are held in a vertical attitude, which minimizes the size of the substrate processing apparatus 1.