This study was focused on the `children`s right to play` in $quot;The Convention on the Rights of the Child$quot;, which was published in 1989 from U.N. and has purpose on finding out general knowledge of kindergarten/day care teachers in three countries: Japan, Korea, and China. There were 113 Japanese, 148 Koreans, and 65 Chinese teachers who were given this survey. We have analyzed the 10 most important factors of ensured children`s right to play by time, place, play tools and facilities, friends, teachers, freedom to choose play and freedom to express oneself through play within three places: kindergarten/day care, home, and community. We have asked the teachers to decide whether to include play in their curriculum and tried to analyze what seemed to be the key word for `the right to play` among teachers. As a result of this study, we find out that teachers, in general, have a good knowledge of the ensured children s right to play, despite the few differences among three countries. It shows that Koreans have the highest knowledge in all three fields: kindergarten/day care, home, and community, when Japanese shows the highest in kindergarten and Chinese at home.