A method of manufacturing an organic light-emitting diode , the method having a substrate preparation step of preparing, by a dry etching method using a particle single layer film as an etching mask, a substrate provided with an uneven structure in which a plurality of concave portions (16 a, b, c; 35 a, b, c) or convex portions (15 a, b, c) are arranged in two dimensions on a surface of the substrate, and a deposition step of depositing, on the uneven structure, at least an anode conductive layer , an electroluminescent layer comprising a light-emitting layer containing an organic light-emitting material, and a cathode conductive layer containing a metal layer, such that the uneven structure is reproduced on a surface of the metal layer on the side of the electroluminescent layer, wherein in the substrate preparation step, the particle mono layer film is formed using a mixture of a plurality of particles having different particle sizes, and a substrate having an uneven structure which satisfies requirements (A) and (B) shown below is prepared: requirement (A): an average height is at least 15 nm but not more than 150 nm, requirement (B): a spectral intensity of a height distribution has a finite value across an entire range in which an absolute value |k| of a wave number is denoted by formula (I) shown below, and an integral value of the spectral intensity across the range accounts for 35% or more of an integral value of the spectral intensity across an entire wave number range: [Mathematical Formula 1] Re 2 ⁢ π λ max ⋅ ε m λ max ⋅ ε d λ max ε m λ max + ε d λ max ≤ k ≤ Re 2 ⁢ π λ min ⋅ ε m λ min ⋅ ε d λ min ε m λ min + ε d λ min wherein ε m (λ) represents a relative dielectric constant of a metal that constitutes the metal layer, ε d (λ) represents an equivalent relative dielectric constant of the electroluminescent layer, λ max represents a maximum extracted wavelength, and λ min represents a minimum extracted wavelength, and Re [ ] denotes a real part of a complex number. requirement (A): an average height is at least 15 nm but not more than 150 nm, requirement (B): a spectral intensity of a height distribution has a finite value across an entire range in which an absolute value |k| of a wave number is denoted by formula (I) shown below, and an integral value of the spectral intensity across the range accounts for 35% or more of an integral value of the spectral intensity across an entire wave number range: [Mathematical Formula 1] Re 2 ⁢ π λ max ⋅ ε m λ max ⋅ ε d λ max ε m λ max + ε d λ max ≤ k ≤ Re 2 ⁢ π λ min ⋅ ε m λ min ⋅ ε d λ min ε m λ min + ε d λ min wherein ε m (λ) represents a relative dielectric constant of a metal that constitutes the metal layer, ε d (λ) represents an equivalent relative dielectric constant of the electroluminescent layer, λ max represents a maximum extracted wavelength, and λ min represents a minimum extracted wavelength, and Re [ ] denotes a real part of a complex number. ε m (λ) represents a relative dielectric constant of a metal that constitutes the metal layer, ε d (λ) represents an equivalent relative dielectric constant of the electroluminescent layer, λ max represents a maximum extracted wavelength, and λ min represents a minimum extracted wavelength, and Re [ ] denotes a real part of a complex number. <EOS>