The invention relates to a method for improving the luminance of an AlGaInP quaternary single-face dual-electrode light-emitting diode with a GaAs substrate. The oxidized DBR layer technology, the electrode structuralization technology, the high current expansion technology, the same-face dual-electrode technology and the like are integrated, LED open circuits or LED half open circuits are avoided, and the dual-electrode light-emitting diode can become a high-luminance same-face dual-electrode light-emitting diode which is high in reflection and free from Joule heat. After the steps of epitaxial growth and electrode manufacture of a high-luminance light-emitting diode chip are completed, the chip undergoes half cutting and finally undergoes one time of oxidization, the conductivity of the DBR layer is changed so that the DBR layer becomes an insulating layer, the reflection ratio is greatly improved, loss caused by generation of the Joule heat, scattering and the like is eliminated, and 100% luminous efficiency is achieved.