There is provided a material that exhibits high solvent resistance after the formation of a cured film, excellent photo-alignment capability relative to a polymerizable liquid crystal, satisfactory heat resistance, and high transparency and moreover, that can be dissolved in a glycol-based solvent, a ketone-based solvent, or a lactic acid ester-based solvent that is applicable to the production of an overcoating of a color filter, during the formation of the cured film. A composition for forming thermoset film having photo-alignment properties, including: a component (A) that is a compound having a photo-aligning group and a hydroxy group; and a component (B) that is a silicon isocyanate compound. A liquid crystal alignment layer formed from the thermoset film forming composition, and an optical device with a retardation layer obtained by use of the thermoset film forming composition.