A joint system includes: a transfer-in/out station capable of holding a plurality of substrates or a plurality of superposed substrates, and transferring-in/out the substrates or superposed substrates to/from a processing station; and the processing station performing predetermined processing on the substrates and joining the substrates together. The processing station includes: a surface activation apparatus activating a front surface of the substrate; a surface hydrophilizing apparatus hydrophilizing and cleaning the front surface of the substrate; a joint apparatus joining the substrates together; and a transfer region for transferring the substrate or superposed substrate to the surface activation apparatus, the surface hydrophilizing apparatus, and the joint apparatus.