The general characteristics of the synchrotron radiation of the permanent magnetic wiggler, and the angular distribution of power and total power radiated for the permanent magnetic wiggler are introduced briefly. After briefly describing the basic structure of the permanent magnetic wiggler, we report the procedure of applying the finite element analysis to the C-shape frame and the integral structure which are the main bearer of the load,in order to determine the displacement of structure of magnet under different conditions. The displacement of the C-shape frame is calculated by the theoretical formula to provide a theoretical basis for further structure design and improvement of the permanent magnetic wiggler.