A protein natural biopolymer, silk possesses novel properties potential for biomedical, cosmetic and pharmaceutical applications among others. For such functions, Bombyx mori fibroin can be regenerated into gel, film, powder and fibers. In this study, B.Mori fibroin was regenerated into films and electrospun nano fibers, and their secondary structure was evaluated. Two aqueous salts (LiBr and CaCl2) were fixed and used to dissolve silk fibroin, and their relative effect presented. Fourier transform infrared spectroscopy (FTIR) and Wide angle x-ray diffraction (WAXD) results showed that untreated regenerated fibroin in film and nanofibers were generally amorphous. It was thus concluded that the regeneration process has a remarkable effect on the molecular weight and crystallinity of fibroin.