AbstractA new pumping system consisting of ceramic turbomolecular pumps and their ceramic fore-pumps has been studied as the main pumping system of FER since these pumps have been developed at JAERI recently. The turbomolecular pump has a rotor of silicon nitride, which is driven by a gas turbine, oil free gas bearings and a non-contact spiral groove seal. The effects of neutron radiation, heat loads and magnetic fields on the ceramic pumps are evaluated based on the FER design conditions.