Since the first quarter of the 20th century, with the local dialects being the written language in Turkistan, Chagatay Turkish gradually gave its place to New Uygur Turkish in East Turkistan. As it is known, Chagatay Turkish is the common spoken and written language of all Central Asian Turkish from the 15th century to the beginning of the 20th century. From the beginning of the 20th century, it is seen that regional written languages have been created in Turkistan with the influence of political authorities. For the New Uyghur Turkish, which continued the tradition of Chagatay written language based on the Arabic alphabet until the beginning of the 20th century, the intellectuals of the region believed in the necessity of a reform in writing and started new searches. Later, political officials in the region were included in this and new writing systems were tried many times from the early 1920s to the 1980s. Finally, the new writing system, which was organized by the Language-Writing Service Committee established in Urumqi, Uyghur Autonomous Region in northwest of China, in 1982 and formed by the improvement of the Arabic alphabet, was approved in 1983 and this writing system has been used since 1984. In this article, the alphabet changes made by the Uyghur Turks living in East Turkistan since the first quarter of the 20th century and the situation of the “ı” sound, which is used by the New Uyghur Turks today but has no equivalent in the alphabet they use, will be discussed.