A low-reflection film-coated transparent substrate comprising a transparent substrate and a low-reflection film formed on at least one principal surface of the transparent substrate, wherein the low-reflection film is a porous film comprising: fine silica particles being solid and spherical and having an average particle diameter of 80 to 150 nm; and a binder containing silica as a main component, the fine silica particles being bound by the binder, the binder further contains an aluminum compound, the low-reflection film contains as components: 55 to 70 mass% of the fine silica particles; 25 to 40 mass% of the silica of the binder; 0.1 to 1.5 mass% of the aluminum compound in terms of Al 2 O 3 ; and 0.25 to 3% of an organic component, the low-reflection film has a thickness of 80 to 800 nm, a transmittance gain is 2.5% or more, the transmittance gain being defined as an increase of average transmittance of the low-reflection film-coated transparent substrate in a wavelength range of 380 to 850 nm relative to average transmittance of the transparent substrate uncoated with the low-reflection film in the wavelength range, and the organic component comprises at least one selected from the group consisting of a β-ketoester and a β-diketone, wherein the aluminum compound is an aluminum chelate complex, the aluminum chelate complex contains at least one polydentate ligand selected from the group consisting of a polydentate ligand having a β-ketoester structure and a polydentate ligand having a β-diketone structure, and wherein the aluminum chelate complex further contains one or two alkoxy groups directly bonded to the aluminum atom. the low-reflection film is a porous film comprising: fine silica particles being solid and spherical and having an average particle diameter of 80 to 150 nm; and a binder containing silica as a main component, the fine silica particles being bound by the binder, the binder further contains an aluminum compound, the low-reflection film contains as components: 55 to 70 mass% of the fine silica particles; 25 to 40 mass% of the silica of the binder; 0.1 to 1.5 mass% of the aluminum compound in terms of Al 2 O 3 ; and 0.25 to 3% of an organic component, 55 to 70 mass% of the fine silica particles; 25 to 40 mass% of the silica of the binder; 0.1 to 1.5 mass% of the aluminum compound in terms of Al 2 O 3 ; and 0.25 to 3% of an organic component, the low-reflection film has a thickness of 80 to 800 nm, a transmittance gain is 2.5% or more, the transmittance gain being defined as an increase of average transmittance of the low-reflection film-coated transparent substrate in a wavelength range of 380 to 850 nm relative to average transmittance of the transparent substrate uncoated with the low-reflection film in the wavelength range, and the organic component comprises at least one selected from the group consisting of a β-ketoester and a β-diketone, wherein the aluminum compound is an aluminum chelate complex, the aluminum chelate complex contains at least one polydentate ligand selected from the group consisting of a polydentate ligand having a β-ketoester structure and a polydentate ligand having a β-diketone structure, and wherein the aluminum chelate complex further contains one or two alkoxy groups directly bonded to the aluminum atom. <EOS>