In this study, a novel silk fibroin films with robust mechanical properties was fabricated by dissolving silk under ultraviolet light (Uv-light) in ionic liquid. Uv-light irradiation can promote the transformation of the silk fibroin structure from the a-helix to the beta-sheet, thereby the strength of the film was enhanced. The wavelength of the Uv-light, the irradiation time and the distance from the light source all have an effect on the strength of the silk fibroin film. Under the optimum conditions, the strength of silk fibroin film could reach 23.7Mpa, which was nearly 85% higher than that of the conventional system. In the meantime, the wettability and swellability of the film were investigated. The results showed that groups with oxygen atoms on the surface of silk fibroin film increased after irradiation, and its wettability and swellability increased significantly, which was more conducive to cell adhesion. Furthermore, the silk fibroin film exhibit excellent biocompatibility, supporting L-929 (mouse fibroblasts) adhesion and proliferation. The study provides a new direction for the preparation of high-strength silk fibroin films, as well as its application in life sciences.