Abstract
With the growth of the internet, research on the influence of internet use on psychiatric symptoms is increasing. “Gamin disorder”, which is a diagnostic criterion for mental illness, was included in ICD-11. However, there are few studies on Japanese. In this study, we conducted a questionnaire survey for 1,366 university students and investigated the current status of problematic Internet use among Japanese young adults and the relationship between PIU and psychiatric symptoms, sleep, social function, and happiness. As a result, it was found that PIU is also recognized in young adults in Japan at the same rate as in the previous studies in other countries. In future it is necessary to conduct research evaluating PIU more objectively.