A first transfer apparatus unloads and transfers substrates from a cassette. A first accommodating unit accommodates the substrates. First substrate processing units divided into at least two groups and arranged in a height direction performs a process to the substrates. Second accommodating units respectively corresponding to the groups are arranged to be parallel with the first accommodating unit in the height direction. Second transfer apparatuses respectively corresponding to the groups unload and transfer the substrates from the second accommodating units corresponding to the same groups into the first substrate processing units of the same groups. Second substrate processing units respectively corresponding to the groups are arranged to be parallel with the first and second accommodating units in the height direction. A delivery apparatus delivers the substrates between the first and second accommodating units and transfers the substrates between the first accommodating unit and the second substrate processing units.