Avempace (c.?1085 - 1138) is the Latinate form of Ibn Bajja; full name Abu Bakr Mu?ammad Ibn Yahya ibn as-Saiigh at-Tujibi Ibn Bajja al-Tujibi; a medieval Andalusian Arab. His writings include works regarding astronomy; physics; and music; as well as philosophy; medicine; botany; and poetry.

He was the author of the Kitab al-Nabat ('The Book of Plants'); a popular work on botany; which defined the sex of plants. His philosophic ideas had a clear effect on Ibn Rushd (Averroes) and Albertus Magnus. Most of his writings and books were not completed (or well-organized) because of his early death. He had a vast knowledge of medicine; mathematics and astronomy. His main contribution to Islamic philosophy is his idea on soul phenomenology; which was never completed.