Şehzade Mehmed Orhan Efendi was an Ottoman prince and the 42nd head of the Ottoman dynasty from 1983 to 1994. He was the advisor of King Zog I of Albania and succeeded as head of the Ottoman dynasty on 9 December 1983, following the death of Şehzade Ali Vâsib.

The Ottoman dynasty consisted of the members of the imperial House of Osman, also known as the Ottomans. According to Ottoman tradition, the family originated from the Kayı tribe branch of the Oghuz Turks, under Osman I in northwestern Anatolia in the district of Bilecik, Söğüt. The Ottoman dynasty, named after Osman I, ruled the Ottoman Empire from c. 1299 to 1922.