A substrate treating apparatus includes a treatment housing, a holder, and a liquid supplying unit. The holder is accommodated in the treatment housing. The holder holds a substrate. The liquid supplying unit is accommodated in the treatment housing. The liquid supplying unit supplies a treating liquid to the substrate held by the holder. The substrate treating apparatus further includes two exhaust pipes. The exhaust pipes are each located on a lateral side of the treatment housing. The exhaust pipes each exhaust gas. The substrate treating apparatus includes a switching mechanism. The switching mechanism is located at a level equal to that of the treatment housing. The switching mechanism switches an exhaust path of the treatment housing to one of the two exhaust pipes.

A substrate treatment line is disclosed. The substrate treatment line may include a chamber portion including a plurality of treatment chambers stacked in a vertical direction, and a vertical return robot, including a plurality of gripping portions, to transfer a plurality of substrates in a vertical direction simultaneously and load or unload the substrates to the treatment chambers.

Disclosed is an apparatus for processing a substrate and an apparatus for transferring a substrate. The apparatus for processing the substrate includes: an index module including a load port on which a container containing a substrate is placed and an index robot that loads or unloads a substrate into or from the container placed on the load port; and a processing module for processing the substrate transferred from the container placed on the index module, in which the processing module includes: a buffer unit on which the substrate is placed temporarily; and a main transfer robot for transferring the substrate between the buffer unit and a processing chamber that processes the substrate, the index robot is provided to approach the buffer unit, and the buffer unit includes: a plurality of buffers which is stacked on each other and supports the substrate; and an interval changing unit for changing an interval between adjacent buffers among the buffers.