The purpose of this study was to explore the relationship between on-line games and moral differences for fifth and sixth graders in Tainan City. The subjects of this study were 672 fifth and sixth graders in Tainan City. ”The Elementary School Students Conduct On-line Gaming Performance with Everyday Life Experience Investigation” was developed and administered as the research instrument. The findings of the study were as follows:1. In the dimension of whether playing online games, there were more than ninety percent students playing on-line games.2. The fifth and sixth graders' morality reached to middle level, whether in whole or in different dimensions, in particular, the internal moral had the highest performance level.3. The fifth and sixth graders' morality had degree influence on involvement in different online games.