Costume plays have been of interest to young people in the recent years. The much increased interest in costume plays has prompted many researchers to verify the behavior characteristics of costume players Despite the importance of the costume play, there has been no systematic study of it. The purpose of this study is to demonstrate the influence of life style on behavior characteristics of the costume player. The subjects of this study were members of the web sits(www.cosmaker.com). A total of 155 subjects responded to the questionnaires and the 143 responses were used for further data analysis. The data was analyzed by factor analysis, cluster analysis, and one-way ANOVA. These were the results of the stud: First, costume player groups are classified into three sub-dimensions: other people-oriented, show-off oriented, and exclusive ego oriented. Second, the behavior characteristics of costume player are significantly shown among those groups.