Abstract: The auxiliary bearings were used to support the rotor when the active magnetic bearing fails to work in the dynamoelectric system of helium turbine of the 10 MW High-Temperature Gas-Cooled Reactor (HTR-10GT). It is the important safeguard for the whole rotor system. The study status of auxiliary bearing was summarized in the paper. For the test rig of auxiliary bearings, the structure characteristic of the cage for the auxiliary rolling bearings was discussed by the finite element method. The result has important reference value for the auxiliary bearing design of HTR-10GT.