Transparency and insolubility of eardrum patch against exudates are important for otolaryngological surgery. The author prepared silk fibroin (SF) films with various concentrations and temperature and then examined solubility and conformation of SF films. SF films were transparent regardless of the various preparation conditions. Although most SF films are soluble in 1X PBS solution at $37^{circ}C$ for 1 h, the SF film with 3.4% with $60^{circ}C$ was insoluble. Scanning electron microscopy (SEM) showed that the SF films have solid and smooth surface. Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) results showed that the conformation of SF films was influenced by the preparation conditions including SF concentration and casting temperature. In conclusion, SF membrane with transparence and insolubility against exudates could be considered as eardrum patch resources.