The Battle of Lalakaon () or the Battle of Poson (or Porson) () was fought in 863 between the Byzantine Empire and an invading Arab army in Paphlagonia (modern northern Turkey). The Byzantine army was led by Petronas, the uncle of Emperor Michael III (r. 842–867), although Arab sources also mention the presence of Emperor Michael himself, while the Arabs were led by the emir of Melitene (Malatya), Umar al-Aqta (r. 830s–863).