The period of Old Anatolian Turkish begins with the settlement of Oghuzes in Anatolia. Oghuz dialect, which was used as a spoken language in the past, has become a written language in Anatolia over time. With the encouragement of Anatolian Turkish Beys, poets and writers of the period wrote many works of copyright and translation. One of these works, “Esrârnâme”, which was written by the Iranian poet and sufi Fer?düddin Attâr in the 12th century, was translated by Ahmed? from Tabriz for the first time in the 15th century. However, it is a translation of the much-loved Huzûr?, which is more similar to Attâr’s “Esrârnâme”. Our work, on the other hand, is the work that was written by Derviş Mustafa from Edirne in the 16th century. In our study, first of all, information about the Old Anatolian Turkish period was given, then the life, literary character and works of Fer?düddin Attâr, who is the author of the work, were mentioned, and then “Esrârnâme” was introduced. The introduction section consists of examples of the work’s external features, content and orthographic features. Esrârnâme, which is a religious and mystical work, consists of stories with advice. In these stories, verses and hadiths were used, and although each story was independent, unity was ensured among the subjects. There are many idioms and proverbs in the work. In the section of orthographic features, how vowels and consonants are used in words, in the middle and at the end, and how some words are written are shown on examples.

Feridüddin Attâr, Esrârnâme, Old AnatolianTurkish, spelling, manuscripts