The Uyghur Arabic alphabet (Uyghur: ئۇيغۇر ئەرەب يېزىقى, romanized: Uyghur Ereb Yëziqi, abbr. UEY) is a version of the Arabic alphabet used for writing the Uyghur language, primarily by Uyghurs living in Xinjiang Uyghur Autonomous Region. It is one of several Uyghur alphabets and has been the official alphabet of the Uyghur language since 1982.
The first Perso-Arabic derived alphabet for Uyghur was developed in the 10th century, when Islam was introduced there. The alphabet was used for writing the Chagatai language, the regional literary language, and is now known as the Chagatay alphabet (Uyghur: كونا يېزىق, romanized: Kona Yëziq, lit. 'old script'). It was used nearly exclusively up to the early 1920s. This alphabet did not represent Uyghur vowels and according to Robert Barkley Shaw, spelling was irregular and long vowel letters were frequently written for short vowels since most Turki speakers were unsure of the difference between long and short vowels. The pre-modification alphabet used Arabic diacritics (zabar, zer and pesh) to mark short vowels. Also, the ة was used to represent a short [a] by some Turki writers.