Sayf ad-Din Qawsun ibn Abdullah an-Nasiri as-Saqi (1302 – April 1342), commonly known as Qawsun (also spelled Qausun or Qusun) was a prominent Mamluk emir during the reigns of sultans an-Nasir Muhammad (r. 1310–41), al-Mansur Abu Bakr (r. 1341) and al-Ashraf Kujuk (r. 1341–42).