Leo III, Leon III, or Levon III may refer to:
- Leo III the Isaurian (685-741), Byzantine emperor 717-741
- Pope Leo III (d. 816), Pope 795-816
- Leon III of Abkhazia, King of Abkhazia 960–969
- Leo II, King of Armenia (c. 1236-1289), sometimes referred to as Leo III, ruled from 1269-1289.
- Leo III, King of Armenia (1287-1307), ruled from 1303-1307
- Other uses
- Leo A, an irregular galaxy in the constellation of Leo
- The Oath of Leo III, 16th-century painting about the 9th century Pope Leo III
- LEO (computer), the early computer used for commercial business applications.
|This disambiguation page lists articles associated with the title Leo III.
If an internal link led you here, you may wish to change the link to point directly to the intended article.