Saad El-Din Rafik Al-Hariri (Arabic: سعد الدين رفيق الحريري, romanized: Saʿd ad-Dîn Refîk el-Harîrî; born 18 April 1970) is a Lebanese-Saudi politician who served as the prime minister of Lebanon from 2009 to 2011 and 2016 to 2020. The son of Rafic Hariri, he founded and has been leading the Future Movement party since 2007. He is seen as "the strongest figurehead" of the March 14 Alliance.

Hariri served as Prime Minister of Lebanon from 9 November 2009 to 13 June 2011. After three years living overseas, he returned to Lebanon on 8 August 2014 and served a second term as Prime Minister from 18 December 2016 to 21 January 2020. Hariri's surprise announcement of an intent to resign, broadcast on 4 November 2017 on Saudi state TV, has widely been seen as part of the Iran–Saudi Arabia proxy conflict in Lebanon, and triggered a dispute between Lebanon and Saudi Arabia. The resignation was later suspended, following President Michel Aoun's request to "put it on hold ahead of further consultations". On October 29, 2019, amid the 2019–20 Lebanese protests, he announced his resignation, and that of his cabinet. He was designated as prime minister on 22 October 2020, but failed to form a government and resigned on 15 July 2021.

On January 24, 2022, he announced that he will suspend his involvement in political activities and did not run in the parliamentary elections on May 15, 2022.