Jeongjae (呈才: A Dance Performed for Royal Events in Palaces of Joseon Dynasty) is called the flower of palace culture of Joseon Dynasty. Jeongjae of Joseon Dynasty into which the Chinese ancient idea of courtesy and music (禮樂思想) still keeps its tradition through Dance Company of National Gugak Center. This article, focusing on the show aesthetics of Jeongjae and its modernization, seeks for a right conservation of Jeongjae and its modernization as a creative succeeding way of it. In the age between the traditional society and modern society, success of Jeongjae met a huge inflection point. First, it lost its intuitive subjectivity that should wish for peaceful reign of the country because of Japanese occupation. Second, Jeongjae also should look for a new show aesthetics along with appearance of western style theater stage. Jeongjae had been placed in the vertical social order in accordance with social class system but it was incorporated into the capital centered horizontal order along with collapse of Joseon dynasty in the modern era. Jeongjae integrated with the modern western style theater stage was placed in a new mechanism as it was recognized as a performance with commercial values for the anonymous public. Today without dynasty system, Jeongjae exists not as something for rites but as a show performance. The modernization of Jeongjae starts from its existing position of such. What would be the most important value when Jeongjae is seeking for modernization through creative transformation out of its position as a museum heritage of the past? Would it be the spirit of BeopGoChangShin (法古創新: Creation based on Oldie)?