A substrate processing apparatus includes a chamber, a susceptor to receive a substrate and provided in the chamber, a gas supply source to supply a predetermined gas into the chamber, and a high frequency power source to treat the substrate by plasma. The susceptor includes a first ceramics base member including a flow passage to let a coolant pass through, a first conductive layer formed on a principal surface and a side surface on a substrate receiving side of the first ceramics base member, and an electrostatic chuck stacked on the first conductive layer and configured to electrostatically attract the wafer received thereon. A volume of the flow passage is equal to or more than a volume of the first ceramics base member. The high frequency power source is configured to supply high frequency power to the first conductive layer.