The substrate supporting table includes a supporting plate that supports a substrate, a peripheral wall that encompasses a flow path of a coolant under the supporting plate and has an upper end enclosed by the supporting plate, a lower cover that encloses a bottom portion of the flow path and encloses a lower end of the peripheral wall. The substrate supporting table further includes a coolant supplying component that supplies a coolant through an upstream input of the flow path, a discharging component that discharges the coolant through a downstream output of the flow path, and a partition disposed between a supplying hole of the coolant supplying component and a discharging hole of the discharging component. A gap is formed between the partition and the bottom portion of the flow path.