Abdullah I bin Al-Hussein (Arabic: عبد الله الأول بن الحسين, Abd Allāh al-Awwal bin al-Husayn, 2 February 1882 – 20 July 1951) was the Founder and Monarch of Jordan from 11 April 1921 until his assassination on 20 July 1951. He was Emir of Transjordan, a British protectorate, until 25 May 1946, after which he was King of an independent Jordan. As a member of the Hashemite dynasty, the royal family of Transjordan/Jordan since 1921.

Born in Mecca, Hejaz, Ottoman Empire, Abdullah was the second of four sons of Hussein bin Ali, Sharif of Mecca, and his first wife, Abdiyya bint Abdullah. He was educated in Istanbul and Hejaz. From 1909 to 1914, Abdullah sat in the Ottoman legislature, as deputy for Mecca, but allied with Britain during World War I. During World War I, he played a key role in secret negotiations with the United Kingdom that led to the Great Arab Revolt against Ottoman rule that was led by his father Sharif Hussein. Abdullah personally led guerrilla raids on garrisons.Abdullah became emir of Transjordan in April 1921. He upheld his alliance with the British during World War II, and became king after Transjordan gained independence from the United Kingdom in 1946. In 1949, Jordan annexed the West Bank, which angered Arab countries including Syria, Saudi Arabia and Egypt, which all defended the creation of a Palestinian state. He was assassinated in Jerusalem while attending Friday prayers at the entrance of the Al-Aqsa mosque by a nationalist Palestinian in 1951. He was succeeded by his eldest son Talal.