Hayrullah Efendi (26 October 1818 – 25 December 1866) was an Ottoman historian, medical doctor, and statesman, who served as the Ottoman ambassador to Iran from 1865 until his death.
He was born on 26 October 1818 to Abdulhak Molla, a renowned physician, from the well-known Hekimbaşılar ulema family in Constantinople, Ottoman Empire. Hayrullah Efendi completed his medical training in 1843.
Hayrullah Efendi worked for the Ottoman government in several positions. He traveled to Europe due to a medical issue in 1863 and gathered his observations in his Yolculuk Kitabı (lit. 'Journey Book'). He died in Tehran on 25 December 1866. He was buried at the Shah Abdol-Azim Shrine in Ray after a major funeral organized Naser al-Din Shah Qajar (r. 1848–96). His son was Abdülhak Hâmid Tarhan.
Müfredat-ı Tıbbiye fi Beyan-ı Evzaü'l-Edviye
Terbiye ve Tedavi-i Etfal (Sıhhatnüma-i Etfal)
Akün, Ömer Faruk (1998). "Hayrullah Efendi". TDV Encyclopedia of Islam, Vol. 17 (Hayal – Hi̇lâfi̇yat) (in Turkish). Istanbul: Presidency of Religious Affairs, Centre for Islamic Studies. pp. 67–75. ISBN 978-975-389-444-9.
Kalın, İbrahim (16 July 2015). "Hayrullah Efendi". In Leaman, Oliver (ed.). The Biographical Encyclopedia of Islamic Philosophy. Bloomsbury Publishing. pp. 143–144. ISBN 9781472569462.
Özaydın, Zuhal (1995). "Tanzimat Devri Hekimi Hayrullah Efendi Hayati ve Eserleri II" [Hayrullah Efendi, a physician of the Reformation Period (Tanzimat): his life and works]. Yeni Tıp Tarihi Araştırmaları (in Turkish). 1: 98–132. PMID 11625088.