Goseong Ogwangdae started academic research in the late 1950s and was designated as a national intangible cultural asset in 1964. From the time of the academic survey to the time of designation, it was recorded as using paper masks, but when the recording image was filmed in 1965, it was already changed to wooden masks. In 1960, before being designated as an intangible cultural asset, the number of masks, which was 9 points, gradually increased to 19 points in 1964. It is necessarily included in the leper, Chorani, Malttuki, Cheongbo-Yangyang, Halmi, and Jemilju, but the character of the yangban is not yet clearly differentiated. Hwangbongsa and Sangju appeared as bare faces, and consumption, milling, Cheongbo-Yangyang are used together with Bibi and inspiration. It can be guessed that Bibi was not the appearance of a foreign object with horns as it is now, considering that Bibi and Madangsoi were used together. Since 1965, shortly after the designation, the whole of the Goseong Ogwangdae mask has been changed to a wooden mask. All the characters except for resident, courtyard, and top-of-the-line are wearing masks. Bibi, Hongbaek, and service masks have never appeared until 1964. The Yangban was changed to the closing ceremony with six people in the order of Won-Yangban, Baekje, Heukje, Cheongje, Hongbaek, and Jonggadoryong. Starting in 1969, the mask enters the stable period where the kind is the same as the present. Bibi-Yangban uses both the Won-Yangban and the Jemilju uses the Somu, but all other characters use the individual mask to use a total of 18 masks. The Yangbans are clearly differentiated, and a total of seven Yangban appear. The reason why the change in the type of mask and the expression of material is so large is that the first generation of mask makers died and the tradition of mask production was cut off, but there is also a cause of the extreme change in the environment of the drama that the performers who joined after the designation had to face. Also, it is closely related to the change of the times when the meaning and weight of masking in masking has changed. At that time, the performers were not so tied to the current concept of 'original form' that they preserved the appearance of the designated time. Originally, Goseong Ogwangdae was centered on improvisation dance, not the formalized dance as it is now, and there was a certain fluid aspect in the retelling, so it was flexible in the use of masks even before the designation of cultural assets. Strict rules did not apply in the details, as it was a self-sufficient play by the performers, not an offer event. The form and contents of this fluid play are changed to preparation for the performance while preparing for the folk art contest. As the subject of the contest in self-sufficient play, dance, costumes, and props became more and more colorful as well as dancing, costumes, and props. As a result, participation in the contest brought about changes in the overall performance and changed the mask, which was accepted within the preservation society.