Behistî Ahmed Celebi, who is amongs the poets and historians of the 16.century, was brought up in the palace of the II. Bâyezîd and he served the sultan. In Turkish literature Behistî is known as a poet who wrote the first Turkish khamse. His khamse is composed of Leyla ve Mecnûn, Mahzenu’l-esrâr, Mihr u Musteri, Iskendernâme and Heft Peyker mathnawis. The author also has a dîvân. He is morewell-known with literary personality but Behistî is also a good historian. He wrote a historical text from beginning of the Ottoman state to mid reign of Sultan Bâyezîd II. There is a separate section for each sultan in his historical text. So his Ottoman history consists of eight sections. We have a copy of Behistî’s history covering Yıldırım Bâyezîd, Celebi Mehmed, II. Murad, Fatih Sultan Mehmed and II.Bâyezîd parts. But until recently a copy of the first part of the work including the first three sultans time could not been found. Finally with the last research we have identfied a copy of the missing part of the work. This copy is very important in terms of it completing the missing part of Behistî's history. Osman Gazi’s section of history is especially notable because it has new information about the author's life and work. In this article firstly we are going to give information about that new copy. After that original information about the authors life and his work, which can be found in the new copy, will be examined. Finally we will try to evaluate the text in terms of historical and literary value