Disclosed is an optical waveguide-forming curable resin composition and optical waveguide-forming curable dry film which are capable of forming cured resin articles that have high heat resistance, excellent mechanical strength and high transparency, and possess properties required for forming optical waveguides, such as low thermal expansion, low transmission loss, etc.The present invention provides a curable resin composition for forming an optical waveguide, the composition comprising a hydrolyzable silyl-containing silane-modified epoxy resin (A) having an average of at least one hydrolyzable silyl group and an average of at least one epoxy group per molecule; and a resin (B) having, per molecule, an average of at least one functional group that is reactive with an epoxy group; and an optical waveguide-forming curable dry film formed using the resin composition.