Mykola Stsiborskyi (Ukrainian: Микола Сціборський), also may be spelled Stsiborsky, Stsyborsky, Ściborski, or Sciborski (1897 – August 30, 1941) was a Ukrainian nationalist politician who served on the Provid, or central leadership council of the Organization of Ukrainian Nationalists (OUN), and who was its chief theorist. He sided with Andriy Melnyk when the OUN split into two hostile factions, and was likely murdered by followers of Melnyk's rival Stepan Bandera.