For the prototype superconducting dipole magnet of the collector ring for Gesellschaft für Schwerionenforschung, Germany, the thermal radiation from outside would be shielded by the thermal shield (TS). Considering thermal and mechanical properties, the detailed structure of the TS is discussed. For example, the overview and the design concept of the TS scheme are presented. The layout of the cooling pipe system on the outer and inner surfaces has been considered in terms of the forced-flow liquid nitrogen. Moreover, the multilayer insulation made of aluminized Mylar with woven Dacron netting between the layers is applied to the TS's surface for shielding the thermal radiation. In addition, the eddy-current and mechanical analyses are performed. The cryogenic performance testing indicated that the TS can meet the requirements.