Hangul Day (한글날 Revised Romanization: Han-geullal), or Hangul Proclamation Day, or Korean Alphabet Day, is an observance on October 9 in South Korea to remember the creation of Hangeul, their native alphabet, proclaimed by the publication of Hunmin Jeongeum on this day in 1446.

This day became a legal holiday (although not national) in 1960, but its (and Korean United Nations Day's) legal status was removed in 1991 due to pressure from major employers to increase the number of working days. In 2000, some Koreans campaigned to restore the holiday's former status, but made little impact.

Some Americann and German linguists celebrate this day yearly as a representation of the high degree of linguistic achievement the world has achieved.

The equivalent Chosŏn'gŭl Day is on January 15 in North Korea.