Abu Saʿīd Abdul-Hay ibn Dhaḥḥāk ibn Maḥmūd Gardēzī, Gardīzī or Gurdēzī (died c. 1061 CE) (Persian: ابوسعید عبدالحی بن ضحاک بن محمود گردیزی) was from Khurasan (in modern Afghanistan). He was a Persian Muslim geographer and historian of the early 11th century from Gardēz. He wrote the book Zayn al-Akhbār while at the court of Abdul-Rashid, sultan of the Ghaznavid empire. Gardēzī's work, written in Persian, is an Islamic history of Central Asia and Eastern Persia and Hungary.
In his Zayn al-akbar, Gardīzī took a dispassionate view of history which was fairly remarkable for its time. It consisted of a history of the pre-Islamic kings of Persia, Muhammad and the Caliphs until the year 1032. Included is a history of the Arab invasion of Khurasan, which it is believed Gardizi was using al-Sallami as a source. His history concerning the Turks was written using Ibn Khordadbeh, al-Djayhani and Ibn al-Mukaffa as sources. He may have been a student of al-Biruni, since the Zayn al-akbar contains information concerning Indian festivals. His style of Persian is simple but mature and provides one of the classical examples of Persian prose-writing. A critical edition was published by ʿAbd al-Ḥayy Ḥabībī, Tehran, 1347 Š./1968 under the title of "Tarikh-e Gardizi".