Based on the new concept of advance thermal analysis and design for electronic equipment, the thermal behavior of the power components and the printed circuit board (PCB) in an opening cabinet are simulated numerically using calculation fluid dynamic method. Temperature values and their profiles on the face of PCB and power supply are obtained, and so are their spatial modes in cabinet. The results are discussed and analyzed, which provides a theoretical basis for optimizing and improving the thermal design of the electronic equipment. The research shows that the advance thermal design for electronic equipment, compared to the traditional one, is easy in operation, advantageous to optimization and of low cost.