Abd al-Rahman ibn Muhammad ibn al-Ash'ath (died 704), commonly known as Ibn al-Ash'ath after his grandfather, was a prominent Arab nobleman and military commander during the Umayyad Caliphate, most notable for leading a failed rebellion against the Umayyad viceroy of the east, al-Hajjaj ibn Yusuf, in 700–703.
Ibn al-Ash'ath was a scion of a noble family of the Kinda tribe that had settled in the Arab garrison town of Kufa in Iraq. He played a minor role in the Second Fitna (680–692) and then served as governor of Rayy. After the appointment of al-Hajjaj as governor of Iraq and the eastern provinces of the Caliphate in 694, relations between al-Hajjaj and the Iraqi tribal nobility quickly became strained, as the policies of the Syria-based Umayyad regime aimed to reduce the Iraqis' privileges and status. Nevertheless, in 699, al-Hajjaj appointed Ibn al-Ash'ath as commander of a huge Iraqi army, the so-called "Peacock Army", to subdue the troublesome principality of Zabulistan, whose ruler, the Zunbil, vigorously resisted Arab expansion. In 700, al-Hajjaj's overbearing behaviour caused Ibn al-Ash'ath and the army to revolt. After patching up an agreement with the Zunbil, the army marched back to Iraq. On the way, the mutiny against al-Hajjaj developed into a full-fledged anti-Umayyad rebellion and acquired religious overtones.