Asad ad-Din Shirkuh bin Shadhi (Arabic: أسد الدين شيركوه بن شاذي, Shêr-kuh literally means lion of the mountains in Kurdish), also known as Shêrko or "Shêrgo" (died 1169) was an important Kurdish military commander, and uncle of Saladin.
He was originally from a Kurdish village in Armenia near the town of Dvin. He was the son of Shadhi ibn Marwan, a Kurdish ruler, and was the brother of Najm ad-Din Ayyub, the ancestor of the Ayyubid dynasty. The family was closely connected to the Shaddadid dynasty, and when the last Shaddadid was deposed in Dvin in 1130, Shahdi moved the family first to Baghdad and then to Tikrit, where he was appointed governor by the regional administrator Bihruz. Ayyub succeeded his father as governor of Tikrit when Shahdi died soon after. When Shirkuh killed a Christian with whom he was quarrelling in Tikrit in 1138, the brothers were exiled (Shirkuh's nephew Yusuf, later known as Saladin, was supposedly born the night they left). They joined Zengi's army, and Shirkuh served under Nur ad-Din who succeeded Zengi in Mosul. Shirkuh was later given Homs as a vassal state of Mosul.