The Internet is a new technology that has affected the world and provides many benefits to its users. In the same time it became a serious threatening to adolescents’ psychological wellbeing because of their more and more tendencies towards the internet addiction.

To analyze the prevalence of internet addiction amongst secondary school adolescents, and to assess it's association with the levels of depression, anxiety and aggressiveness.

The sample consisted of 226 students of the first and fourth grade from two secondary schools in Tuzla, who at home have access to the Internet. We used the Internet YIAS, BDI, BAI, State trait anger expression inventory – STAXI-2 Staxi.

The adolescents used the most frequently social networks on the Internet. Obtained results showed that 17.3 % of 226 met criteria for Internet Addiction. There were significant positive association of the Internet addiction level with the severity of depression (Pearsons’ 'r”=0,310, P=0,001) and anxiety (Pearsons’ 'r”=0,219, P=0,001) amongst the tested adolescents. On the other side, level of the Internet addiction was not associated with the severity of aggressiveness (Pearsons’ 'r”= -0,018, P=0,791).

Excessive internet use is associated with a variety of psychosocial problems among young people. Internet addiction was positively associated with the depression and anxiety severity, but it was not associated with the severity of aggressiveness amongst school adolescents.