This review deals with chemical, physical and structural studies of tussah (A. pernyi) silk fibroin fibres and films. Structure-performance relationships of both fibers and films will be outlined, the aim being to emphasize the importance of this fibrous biopolymer in the context of the traditional textile uses, and to show the possibility of extending its application in new fields (biotechnology, biomaterials, etc.). In this respect, particular attention will be payed to physico-chemical properties and fine structural features of tussah silk fibroin films. Processes able to induce β-sheet crystallization of random coil/α-helix films, such as immersion in water-miscible hydrophilic solvents and heat treatment at above glass transition temperature, will be reviewed, and kinetics and mechanism of transformation will be discussed on the basis of spectroscopic and thermal measurements.