A famous Japanese poetry contest was held by Yozei, the Retired Emperor, in which his First Prince’s daughters participated, in 948. As a legendary emperor and the oldest emperor at that time, Yozei had been far from politics for nearly 60 years when, in the year before his death, he called his granddaughters to join a friendly family poetry contest, the theme of which was the sentiment of late autumn. Of the several poetry contests held by Yozei in which mainly his family and vassals participated, this was the last. He being a talented poet, his poem was recorded in the most famous poetry collection, the “Ogura Hyakunin Isshu.” This paper aims to analyze the relationship between this poetry contest in which his granddaughters participated and other poetry contests held by Yozei, and to examine the structure of the contest of poetry in return. The purpose of this study is to identify the essence of this contest and to demonstrate its significance in Japanese literature.