This paper attempts to analyze the contemporary perspectives to Old Chosŏn with focus on the system of chronology. The existing scholarships concentrate on dividing periods of Tangun Chosŏn and Wiman Chosŏn with making a denial of "Kija(Chi Tzu) Chosŏn". However, the negation of Kija's proceeding to Chosŏn does not mean the negation of the period of Kija Chosŏn. According to the archaic Chinese documents on the Tung-i(Eastern Barbarian), during the Bronze Age the Yemaek lived in an area stretching from southern Manchuria to the northern Korean peninsula. Therefore, the Bronze Age of Old Chosŏn is more like the period of Yemaek Chosŏn than that of "Kija Chosŏn". In other words, the history of Old Chosŏn is not simply a process of Tangun Chosŏn to Wiman Chosŏn, but rather a succession among three Chosŏn(Tangun Chosŏn-Yemaek Chosŏn-Wiman Chosŏn). The concept of "three Chosŏn" could be derived from chronology of the Chewang Ungi(Rhymed Record of Emperors and Kings) by Yi Sŭnghyu(1224~1300); Chŏn-Chosŏn(Former Chosŏn), Hu-Chosŏn(Later Chosŏn), and Wiman Chosŏn. Therefore, it is inappropriate to define Old Chosŏn only to Tangun Chosŏn. In a strict sense, according to Samguk yusa(Memorabilia of the Three Kingdoms) the history of Old Chosŏn not only possesses the period of Tangun Chosŏn, but also the period of Yemaek Chosŏn(so-called "Kija Chosŏn" or Hu-Chosŏn).