Kwang-su, also spelled Kwang-soo or Gwang-su, is a Korean masculine given name. Its meaning differs based on the hanja used to write each syllable of the name.

There are 13 hanja with the reading "kwang" and 67 hanja with the reading "su" on the South Korean government's official list of hanja which may be registered for use in given names.^[1] Ways of writing this name in hanja include:

• 光洙 (빛 광; bit gwang; 물가 수; mulga su).
• 光守 (빛 광; bit gwang; 지킬 수; jikil su). These same characters are also one possible way of writing the Japanese surname and given name Mitsumori.^[2]
• 光秀 (빛 광; bit gwang; 빼어날 수; pae-eonal su). These same characters are also one possible way of writing the Japanese given name Mitsuhide.^[2]

According to South Korean government data, Kwang-su was the ninth-most popular name for newborn boys in 1945.^[3]

People with this name include:

• List of Korean given names