The purpose of this study is to know the important design element for a public library, after analyzing design concept and organization of space of the prize winner at the architectural competition. To carry out the research, the best 31 works between the year of 2005 and 2010 were collected by the architectural magazine A&C published in every other month. During the research, special characters of each prize winner have been analyzed in the aspect of the design concept and the organization of space. While working on the design concept, a factor that created such concept was successfully figured out, and studying on the organization of space enabled us to know the special characters of the interior space. According to the result of the analysis in this study, the design elements which are selected highly frequent are ordered as follows; (1)organization of space, (2)function & shape, (3)circulation, (4)landscape, (5)symbolic aspect. Through the analysis for the organization of space, I reach a conclusion, the frequent type is a "PM-ES-CJ". The study is anticipated to be helpful in understanding the trends in the field of designing a public library, and it is also likely for an architect to use it as a reference.