Provided is a composition for forming a film, the composition not having completely dissolved hydroxypropyl methyl cellulose (HPMC), and enabling formation of the film having a uniform thickness by suppressing the viscosity increase of the composition around an immersion temperature of 50°C. More specifically provided is a composition for forming a film, the composition comprising hypromellose having methoxy group content of 28.0 to 30.0% by weight and hydroxypropoxy group content of 7.6 to 8.5% by weight, wherein a 2% by weight aqueous solution of the hypromellose provides a viscosity at 20°C of 4.0 to 6.5 mPa·s, a 20% by weight dispersion of the hypromellose provides a viscosity at 50°C of 2,000 to 11,000 mPa·s, and a 20% by weight aqueous solution of the hypromellose provides a gelation temperature of 54 to 57°C; and a solvent.