‘Alī ‘Imādu d-Dīn Nasīmī (Azerbaijani: Seyid Əli İmadəddin Nəsimi عمادالدین نسیمی, Arabic: عمادالدین نسیمی‎), often known as Nesimi, (1369 Unknown) –1417 skinned alive in Aleppo) was a 14th-century Azerbaijani^{[citation needed]} or TurkmenḤurūfī poet. Known mostly by his pen name (or takhallus) of Nesîmî, he composed one divan in Azerbaijani, one in Persian, and a number of poems in Arabic. He is considered one of the greatest Turkic mystical poets of the late 14th and early 15th centuries and one of the most prominent early divan masters in Turkic literary history.

Very little is known for certain about Nesîmî's life, including his real name. Most sources indicate that his name was İmâdüddîn, but it is also claimed that his name may have been Alî or Ömer. It is also possible that he was descended from Muhammad, since he has sometimes been accorded the title of sayyid that is reserved for people claimed to be in Muhammad's line of descent.

Nesîmî's birthplace, like his real name, is wrapped in mystery: some claim that he was born in a province called Nesîm — hence the pen name — located either near Aleppo in modern-day Syria, or near Baghdad in modern-day Iraq, but no such province has been found to exist. There are also claims that he was born in Shamakhi-which is mostly likely because his brother is buried in Shamakhi, Azerbaijan.