This paper examined the creation of Sijo by naturalized poets from the late Goryeo Dynasty to the early Joseon Dynasty. From the late Goryeo to the early Joseon Dynasty, it was the formation of Sijo, where Shinheung-Sadaebu was the main creative class of Sijo. In this phase, naturalized poets also created Sijo, revealing their political position and world awareness. The fact that naturalized poets, who had no choice but to speak poor Korean, created Sijo, a unique Korean song format, is very special in itself.
General Byeon An-yeol from Shenyang, wrote the lyrics of <Bulgulga不屈歌> during the process of replacing the dynasty, expressing his strong loyalty to the Goryeo Dynasty. Seol Jang-su, a native of Uighur who was in charge of diplomacy to Ming China, wrote the lyrics of <Shineonga愼言歌> and warned against caution in his speech and conduct. Lee Ji-ran, who was born in Jurchen and rose to the rank of the Joseon royal family, wrote the lyrics of <Chukrokga逐鹿歌>, expressing concern about the fate of Joseon.
The fact that naturalized poets and high-ranking politicians created Sijo with Chinese poetry from the late Goryeo to the early Joseon indicates that Sijo was recognized as an important literary act in the literary field at that time. At the same time, it can be said that Sijo's creation has a personality that deserves pride as a writer. In addition, the openness of the creation of the sijo was already in place from the formation period.