In the present invention, a plurality of first units capable of accommodating the substrate and a second unit are provided, in which a substrate is carried between the first unit and the second unit. The first units and the second unit are arranged side by side in a plan view, and at least one of the plurality of the first units is a processing unit for performing processing for the substrate. The plurality of first units are arranged in a line in the horizontal direction, and at least two first units adjacent to each other in the horizontal direction of the plurality of first units are movable in the horizontal direction to be able to transfer the substrate to/from the second unit. According to the present invention, the substrate processing system including a plurality of units flexibly deals with various substrate processing recipes and reduces the processing time difference among substrates and the carriage waiting time of the substrate.