Al-Sijistani refers to people from the historic Sijistan region in present-day Sistan, the border region of eastern Iran and southwestern Afghanistan.
Prominent people who have been called Al-Sijistani include:
- Abu Da'ud Sulayman ibn Ash`ath al-Azadi al-Sijistani (817-888 CE), ("Abu Dawūd"), collector of hadith
- Abu Yaqub Sijistani (died c. 971 CE), Neoplatonist and Ismaili missionary
- Abu Sulayman Muhammad al-Sijistani (c. 932 - c. 1000 CE), Islamic philosopher, flourished in Baghdad
- Al-Sijzi (c. 945 - c. 1020 CE), mathematician and astronomer
- Masʽud ibn Muhammad Sijzi, 14th-century Persian physician