This was a descriptive and cross-sectional study conducted with adolescents to examine the correlation between Internet addiction and social phobia. The population of the study consisted of 24,260 students aged between 11 and 15 years. Sampling method was used from population with known number, and 1,450 students were calculated as sample of the study. In this study, 13.7% of the adolescents had an Internet addiction, and 4.2% spent more than 5 hr on the computer every day. There was a positive correlation between Internet addiction and social phobia. The form of time spent on Internet was examined in terms of addiction and social phobia; although Internet addiction was related to games, dating sites, and web surfing, social phobia was related to homework, games, and web surfing. It was hypothesized that adolescents with social phobia were Internet addicts, and the participants used the Internet to spend time rather than socialize.