Odo of Arezzo

Odo of Arezzo or Abbot Oddo (fl. late 10th century) was a Medieval composer and theorist who worked in Arezzo. Little is known about his life, except that he was an Abbot in Arezzo, working under Bishop Donatus of Arezzo. Odo composed a tonary (a book of chants which usually included antiphons and responsories) with a discussion of modes, which survives in 20 manuscripts, four of which contain attributions to Odo. In several of the manuscripts a prologue ascribed in three out of six to Odo is entitled "Formulas quas vobis".

A Dialogus de musica has been mistakenly attributed to Odo of Arezzo.