Turki I bin Abdulaziz Al Saud (Arabic: تركي الأول بن عبد العزيز آل سعود‎‎, Turkī l-ʾAwwal bin ʿAbd al-ʿAzīz Āl Saʿūd) (1900–1919) was the eldest son of King Abdulaziz of Saudi Arabia. He accompanied his father during the conquest of the Arabian Peninsula at a young age, and witnessed battles in Kuwait and Al-Hasa. He was married to Nuwair. In 1918 he had a son named Faisal. He died in 1919 due to flu pandemic which also killed many others in the region also including two of his half-brothers. His brothers who died in the flu pandemic were Saad (I) and Fahd (I). Saad (I) was the younger full-brother of King Faisal. Turki Al Awwal was elder full brother to King Saud.

Turki al Awwal was the eldest son of King Abdulaziz. Turki's birthplace is Kuwait City. He was born in 1900 when his family was in exile there. He was full-brother of King Saud. His full sisters include Princesses Munira and Nura. Their mother was Wadhah bint Muhammad bin 'Aqab, who belonged to the Bani Khalid tribe. She was the daughter of the chief of the Bani Khalid tribe, who ruled Al Hasa and was King Abdulaziz's second wife.

Prince Turki was the deputy of his father as commander-in-chief of the army. During his lifetime, Turki al Awwal was the Crown Prince of Najd, his father's domain until then. He was Crown Prince beginning by his father's conquest of Riyadh on 15 January 1902 up to his own early death in 1919. The Saudi custom of succession stipulates that kings be succeeded by their younger brothers, in seniority of age, rather than by their sons. Therefore, at Turki's death, his next brother Saud became crown prince, rather than his posthumous son, Faisal. Saud later became king and was overthrown by another of his brothers (and not by one of his sons).

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