Ibn Sab'īn (Arabic: محمدبن عبدالحق بن سبعين ʿAbd al-Ḥaqq b. Sabʿīn al-Mursī) was an Arab[1][2] Sufi philosopher, the last[citation needed] philosopher of the Andalus in the west land of Islamic world.

Ibn Sabʿīn is most famously remembered for his replies to the questions sent to him by Frederick II, Holy Roman Emperor and published as الكلام على المسائل الصقلية al-Kalam 'ala al-Masa'il as-Siqiliya (Discourse on the Sicilian Questions)[5] which were first popularised in the West in 1853 by Sicilian Orientalist Michele Amari[6] who recognised Ibn Sab'in as the author, among others, of the responses to the Sicilian Questions.

In addition to the Sicilian Question, his other major work and longest is بد العارف Budd al-Arif (The Essential of the Gnostic), which is extant in manuscript and an edited version.

His writing style has been described as composite and cryptic, which some of the modern publishers had difficulty understanding.

In his work Bud al-'Arif (The Essential of the Gnostic), Ibn Sab'in virulently criticized Averroes and considered him a fanatic Aristotelian who always sought to validate Aristotle's ideas even when they were absurd.