Upon receipt of the substrates W, the substrate transport robot 29 transports the substrates W to the cleaning carrier transfer part 28. More specifically, having a similar structure to that shown in FIG. 8, the pushing stage moves upward from underneath the cleaning carrier WC, and moves downward to store the substrates W into the cleaning carrier WC. This operation is repeated twice for each cleaning carrier so that the substrates W placed on the two turning and pushing-out parts 27 are stored together in one cleaning carrier WC.