A lens-attached light-emitting element having an improved optical availability efficiency includes a composite lens provided on an approximately U-shaped light-emitting area of the light emitting element array. Four spherical lenses are arranged in such a manner that each is centered in the neighborhood the an end of a respective one of three segments of a U-shaped polygonal line corresponding to positions where light emitted by the U-shaped light-emitting area is a maximum Three cylindrical lens are arranged between two of the spherical lens, respectively, each cylindrical lens having an axis parallel with each segment. These four spherical lenses and three cylindrical lenses together constitute the composite lens. The light-emitting element further comprises an antireflection film covering the light-emitting area, and the composite lens is formed on the surface of the antireflection film.