A substrate treating apparatus includes first and second transport mechanisms, an intermediate transport mechanism, first and second intermediate parts, and a controller. The intermediate transport mechanism is disposed between the first and second transport mechanisms. The first intermediate part is disposed within a first overlapped area where the first transport mechanism and the intermediate transport mechanism are capable of transporting a substrate. The substrate is placed in the first intermediate part. The second intermediate part is disposed within a second overlapped area where the intermediate transport mechanism and the second transport mechanism are capable of transporting the substrate. The substrate is placed in the second intermediate part. The intermediate transport mechanism repeats cycle operation based on the controller's control. The cycle operation by the intermediate transport mechanism includes only a first access operation of accessing the first intermediate part and a second access operation of accessing the second intermediate part.