The purpose of the study was to understand of the relationships between the junior high school students’ self-esteem, making friends in internet and enzokousai through internet. In this study, stratified cluster sampling were used to select seven and eight grade students of Hsinchu City Junior High School to conduct a questionnaire survey. 544 valid samples were obtained. The research tools including self-esteem scale, the state of making friends in internet, the attitude assessment of enzokousai through internet and personal basic information. The data was analyzed by statistical methods, independent samples t-test, Pearson product correlation and multiple regression. The main findings are as follows: 1. The overall self-esteem level of junior high school students during the samples is moderate. The cognitive and behavioral performance of making friends in internet is average level, as to the viewpoint is to enzokousai through internet is neutral and the willing to take actions about enzokousai through internet is low. 2. There is no significant difference of junior high school students’ self-esteem between different genders and is also no difference between 7 and 8 grade. 3. The difference only exists in cognition when related to gender and grade in the making friends in internet. And there is significant difference related to gender but not related to grade in the attitude to enzokousai through internet 4. The junior high school students’ self-esteem is not related to the experience of making friends in internet, but is related to the tendency to enzokousai through internet activity. 5. There is difference in attitude about enzokousai through internet of the junior high school students when related to the experience of making friends in internet. 6. The junior high school students’self-esteem and the status of making friends in internet can effectively predict the attitude about enzokousai through internet. According to the results, the researchers provide specific recommendations for parents , educational counselors and education authorities , government agencies to do the research and practice issue.