The Old Turkic script (also known as variously Göktürk script, Orkhon script, Orkhon-Yenisey script) is the alphabet used by the Göktürk and other early Turkic Khanates during the 8th to 10th centuries to record the Old Turkic language. It was mostly replaced by the Arabic script after the adoption of Islam in Volga Bulgaria (922) and Transoxania .

The script is named after the Orkhon Valley in Mongolia, where early 8th century inscriptions were discovered in an 1889 expedition by Nikolay Yadrintsev. These Orkhon inscriptions (Turkish: Orhun Yazıtları) were published by Vasily Radlov and deciphered by the Danish philologist Vilhelm Thomsen in 1893. It was later used by the Uyghur Empire. Additionally, a Yenisei variant is known from 9th-century Kyrgyz inscriptions, and it has likely cousins in the Talas Valley of Turkestan and the Old Hungarian script of the 10th century. The alphabet was usually written from right to left. Further Turkic Nestorian manuscripts, that have the same "rune-like" duct as the Old Turkic script, have been found especially in the oasis of Turfan and in the fortress of Miran.