The purpose of the present study was to investigate the psychiatric symptoms of adolescents with and without Internet use. A total of 2,080 students (1,105 male, 975 female) were recruited for the study. We administered the Symptom Checklist-90-Revision and Questions Related to Internet Use. Students in 10th through 12th grades were recruited from 14 senior high schools in Sivas, Turkey. Data were collected from October to May 2008. Data were analyzed after excluding the participants who provided incomplete data. It was found that Internet use in adolescents was associated with more severe psychiatric symptoms. Attention should be devoted to adolescents with Internet use for the design of preventive strategies.