The possibility of using nonmulberry silk fibroin as a biomaterial is a subject of broad interest due to its inherent RGD sequence. However, the extraction of silk fibroin from cocoons and silk glands remains a formidable task. In this work, we report a facile method to dissolve tussah silk using CaCl2–formic acid and a water-rinsing process for regeneration of tussah silk fibroin (TSF) film. The new technique is important and valuable because it can directly extract silk fibroin from cocoons and is advantageous over other previous reported methods using LiSCN and Ca(NO3)2. The morphology, chemical structure, and mechanical properties of regenerated film rinsed with water, ethanol, and methanol are characterized by scanning electron microscopy, Fourier transform infrared, and X-ray diffraction techniques in combination with mechanical testing. The results reveal that the regenerated TSF films possess a smooth surface and nanostructural cross section and exhibit predominantly β-sheet crystal structure and ...