An Exploratory Study on the Interrelationship of Internet Addiction, Internet Usage Motivation, Internet Usage Behavior and User Characteristics for Taiwan High School Students. Chieh-Ju Tung Abstract The purpose of this study was to examine the interrelationship among motivation and gratification level, activities, personality and Internet addiction for Taiwan¡¦s high school students based on the Uses and Gratifications Theory. The characteristics of those identified as addicted are investigated along with the factors of demographic data, motivation and gratification, web attitude and personality. Moreover, structural equation modeling was used to verify the Theory. The study was conducted using purposive sampling at two major municipals in Taiwan. Questionnaires including Pathological Internet Use Scale for Taiwan high school student, Diagnoistic Questionnaires, Internet usage Motivation and Gratification Scale, Interpersonal Relationship Scale, Self-Esteem Scale, Center for Epidemiologic Studies Depression Scale, Internet Usage Behavior Questionnaire, Perceptions of the Internet Influences and Demographic Data. Of the 1708 qualified samples, 236 were classified as Internet addicted. Major findings of the study are: 1. Entertainment is the major factor for high school students to use Internet, information searching stands as second. Surfing with motivation of social and entertainment has positive correlation with Internet addiction. Those classified as addicted have higher motivation on social and entertainment and have higher satisfaction thereafter. 2. Males who own computer, with grades in lower two-thirds of the class, with more than 4 years Internet usage experience, always using cyber-café or surfing during weekday have higher tendency to become addicted. 3. System and location of school, the grade attended or whether access Internet at home have no relationship with addiction. 4. The average weekly hours on Internet is positive correlated with Internet addiction. 5. Students with personality of dependence, shyness, depression or lower self-esteem have higher tendency to become addicted. 6. The probability of males to become addicted is 2.6 times that of females. Vocational high school students have higher tendency to become addicted than non-vocational high school students. 7. The average weekly hours on Internet for those addicted is 21.2 hours, it¡¦s 1.75 times that of normal ones. 8. Those identified as addicted always surf in cyber-café and favor on-line games, chat room and sex-related activities. 9. Those identified as addicted have lower self-esteem and higher depression. 10. Internet addiction has significant canonical correlation with motivation on social/entertainment and hours on Internet. 11. Internet addiction has significant canonical correlation with shyness, depression emotion, poor interpersonal relationship, negative self-concept and lower self-esteem. 12. The theoretical model constructed in this study could explain the relationship among main variables by Amos. 13. ¡§Internet usage motivation¡¨ has greatest direct effect on addiction. It has greatest total effect when combines with the factor of ¡§Average weekly hours on Internet ¡¨. 14. The predictability for Internet addiction is 62% when six variables were used (Motivation on social, Motivation on entertainment, Average weekly hours on Internet, Interpersonal relationship, Depression and Self-esteem). Finally, suggestions on counseling addicted students are made for government and high school authorities, counselors and parents. Issues for futher study are also discussed.