Provided is a method of conveying a storage container from a placing table to a conveyance place using a conveying mechanism in a substrate processing apparatus. The storage container hermetically stores a substrate and includes a flange portion formed on the top thereof. The conveying mechanism includes a hand portion provided with a flange insertion portion. The substrate processing apparatus is provided with at least two placing tables arranged side by side in a first horizontal direction. The method includes moving the placing table to the conveyance place in the second horizontal direction by a predetermined distance; sliding the hand portion from a side of a placing table neighboring to the placing table in the first horizontal direction such that the flange portion is inserted into the flange inserting portion; and conveying the storage container from the placing table to the conveyance place through the hand portion.