| Hoca Sadeddin Efendi | |
| Birth Date: | 1536/1537 |
| Birth Place: | Constantinople, Ottoman Empire (now Istanbul, Turkey) |
| Death Date: | October 2, 1599 |
| Death Place: | Constantinople, Ottoman Empire |
| Nationality: | Ottoman |
| Occupation: | Islamic scholar, theologian, official, historian |
| Notable Works: | Tâc üt-Tevârîh (Crown of Histories) |
| Shaykh al-Islām | |
| Children: | Mehmed Efendi, Esad Efendi, Mesud Efendi, Abdülaziz Efendi, Salih Efendi |
Hoca Sadeddin Efendi (ota|خواجه سعد الدین افندی; 1536/1537 – October 2, 1599[1]) was an Ottoman Islamic scholar, theologian, official, and historian, a teacher of the future Ottoman sultan Murad III. His name may be transcribed variously, e.g. Sa'd ad-Din, Sa'd al-Din, Sa'düddin, or others. He was also called by the title of "Câmi'-ür Riyâseteyn".[1]
When Murad became Sultan, Sadeddin became his advisor. Later he fell out of favor, but was appointed Shaykh al-Islām, a superior authority in the issues of Islam.
Sadeddin is the author of Tâc üt-Tevârîh (Tadj ut-Tewarikh, “Crown of Histories”), a history of the Ottoman Empire in prose and verse.
He had at least five sons: Mehmed Efendi (died 1615), Esad Efendi (died 1625), Mesud Efendi (died 1597), Abdülaziz Efendi (died 1618), and Salih Efendi.[2]