Constitution Memorial Day (憲法記念日, Kenpō Kinen-bi^?) is a national holiday in Japan. It takes place on May third in celebration of the promulgation of the 1947 Constitution of Japan. It is a part of the collection of holidays known as Golden Week.^[1]

A holiday since the current Japanese constitution came into effect on May 3, 1947, this is the only day of the year that the National Diet Building is open to the public.^[2] Being a day that draws its significance from the Japanese constitution, Constitution Memorial Day is often chosen as a day to reflect on the meaning of democracy and Japanese government. For instance, in 2003, a number of newspapers featured editorials regarding the constitution's embattled Article 9.^[3]