Faisal bin Turki Al Saud (Arabic: فيصل بن تركي آل سعود, romanized: Fayṣal ibn Turkī Āl Suʿūd; 1785 – December 1865) was the second ruler of the Second Saudi State and seventh head of the House of Saud.

Faisal was the son of Imam Turki bin Abdullah. He was one of the members of the Al Saud family who was taken to Cairo following the capture of Diriyah by Ibrahim Pasha, son of Muhammad Ali, in May 1819. Faisal returned to Riyadh in 1827-1828.

In 1830 Faisal was sent on military operations to Al Hasa in the east. In his absence, his father was assassinated by Mishari bin Abdul Rahman, a second-cousin of his father in 1834. Faisal hurried back to Riyadh to deal with the revolt. His troops stormed the castle and killed Mishari. Emir of Jabal Shammar, Abdullah bin Rashid, helped Faisal in this attack. Those not directly involved in the murder were spared and the town pledged allegiance.

Imam Faisal first ruled the Second Saudi State from 1834 to 1838. Then he was forced into exile in Cairo by the Ottomans who sent an expedition to Najd due to his rejection of paying tribute to the Egyptian forces in Hejaz.

Faisal continued to oppose the Ottoman forces, however, and the Egyptian governor of Arabia, Khurshid Pasha, supported a rival candidate - Khalid bin Saud, a second-cousin of Faisal. Khalid was a member of the senior line of the Saud family. Faisal was forced to flee the city and take refuge with the al Khorayef princes of the Bani Tamim tribes. In December 1838, he attempted to come to terms with Khurshid Pasha, but was forced to return to captivity a second time in Cairo. He was accompanied by his younger brother Jiluwi, his sons, Abdullah and Muhammad, and his cousin, Abdullah bin Ibrahim bin Abdullah, a son of his uncle. In 1843, he was released in Cairo and returned to Riyadh following the total withdrawal of the remaining Egyptian troops from Najd in 1841.

Following his return to Riyadh, Faisal reclaimed the throne in 1843 and ruled until 1865. He easily defeated his third-cousin Abdullah bin Thunayan, who had revolted against the ineffective Khalid and taken control. Faisal depended on a close alliance with the Al Rashid family of Ha'il. Abdullah bin Rashid played a key role in his success, and the two families were extensively intermarried. Early in his reign, Faisal appointed Abdullah as the Amir of Ha'il in 1835 in return for his loyalty. In his second term, Faisal also established cordial relations with the Ottomans who appointed him governor of Najd. In turn, Faisal recognised the supremacy of the Ottoman Empire in the region.

Faisal consolidated his power by subduing opposition tribes in Najd. This centralized authority required financial resources, prompting Faisal to target Al-Ahsa, Qatif, and Saihat—key economic hubs. He imposed his control over these regions, ensuring a steady flow of funds to his treasury by imposing what was termed zakat, though it functioned as a tax in contemporary terms.

Faisal's ambitions extended beyond these territories. In 1847, he attempted to intervene in Bahrain, exploiting internal conflicts within the ruling family. Although unsuccessful in capturing Bahrain, he settled for a peace agreement that included a tribute payment. His inability to seize Bahrain was primarily due to attacks on the Al-Qassim Province by Muhammad bin Awn and Khalid bin Saud, and the firm stance of the British government against Saudi expansion in the Persian Gulf. The British, who had substantial interests in the region, closely monitored Faisal's movements. Their support for the Bahraini sheikh and their strategic positions in the Gulf influenced the broader regional dynamics.