The Aegean islands began to come under Ottoman rule with the conquest of those close to the Anatolian coast from the 15th century. The island of Thassos, located in the Northeast Aegean ıslands and located in the far North of the Aegean Sea has strategic importance in many aspects, espeacially its proximity to land. Musa Kâzım Bey, known as historian, geographer, educator and administrator, one of the scientists and administrators of the Second Constitutioan period, wrote many books and articles on history and geography. One of these articles is titled History of Thassos, puplished in the Journal of Tarih-i Osmani Encümeni in 1913.This article is a very important source in terms of shedding light on both the general history of the island of Thassos and the history of Thassos in that period, where Musa Kâzım Bey was personally as a governor. In his article, Musa Kâzım Bey provides important information about the geographical, administrative, political and economic history of Thassos. In addition, in this article, with a Kânunnâme of Thassos dated 1672 and there is a conveyance (mülknâme) documenting that Sultan Mahmud II bestowed Thassos on Mehmed Ali Pasha.