A Helium refrigeration system has been constructed for a superfluid-cooled 21 T superconducting magnet and a 15 T superconducting outer magnet of 40 T class hybrid magnet. The refrigeration system was designed for the application of two refrigeration modes, that is, superfluid cooling mode, and pool boiling cooling mode. The refrigeration power of 450 W at 4.4 K was obtained successfully.