Mar Eliya IV (or IV) was the patriarch of the Church of the East from 1405 until 1425. His reign falls in a period of obscurity owing to the limited contemporary evidence.
He appears in a contemporary list of patriarchs in a 15th-century manuscript copy of the Book of the Bee between two patriarchs named Shemÿon. Traditionally these are Shemÿon III and Shemÿon IV, but David Wilmshurst has argued on the basis of the aforementioned manuscript that there was only one Shemÿon between Denha II and Eliya IV, and that this must be Shemÿon II. He suggests placing Shemÿon III after Eliya IV.
In view of the upheavals in Iraq in his time, it is unlikely that he was consecrated in Baghdad. Probably he was consecrated and resided in a monastery in northern Iraq. Traditionally his death has been placed in 1437, since in that year a patriarch named Shemÿon is mentioned in a dating clause in a manuscript colophon. A colophon in a manuscript copied by the scribe Masÿud of Kfarburan, dating to 1429/30, also mentions a patriarch Shemÿon, which would push back Eliya's death date to the 1420s.