Youngest Composer of a Musical

Adám Lörincz; Hungary; August 16, 2002.

Adám Lörincz (Hungary, b. 1 June 1988) was aged 14 years 76 days when his 92-minute musical, Star of the King was performed on August 16, 2002 in Szekesfehervar, Hungary.

Source: Guinness World Records 2007