The resistive power leads of a high temperature superconducting (HTS) rotor field coil are located in vacuum near the rotor axis and are cooled by thermal conduction to the return flow path by bonding the leads to the tubing bulkhead through ceramic insulators. The lead length, cross-section and electrical resistivity are optimized for minimum heat conduction and ohmic resistance heat transfer to the cold gas. Thermal expansion or contraction of the leads is accommodated by flexible sections at the warm and cold end of the leads.