We investigated factors that influence adolescents' engagement in risky Internet behavior, in particular the factors relating to negative impacts on adolescent development: social interactions, sexual activity, and their emotional development. Material and method: All the students, aged between 15 to 18 years old, come from 7 high schools of Iasi, Romania. The authors examined risk factors of teens internet use at 283 teenagers, who had been involved in an online activities and completed a survey to assess relationships among development and (a) amount of Internet use (with the identification of a possible computer addiction), (b) the interference of excessive use with school grades and social life, sexual activity, and their emotional development. Results indicated that the following factors were found to be predictors of adolescents development: frequency of Internet use, parental rules, type of personal information given out, frequency of chatting, inappropriate websites have been visited, and type of internet advice heard. Conclusion: Our results showed a significant positive correlation between measures of Internet use and time spent online for the Internet. Implications for and development as impacted by social support networks, are discussed. Finally, Internet use was associated with identity status. These results suggest that the Internet may be an important aid for teenager as they searched for an young identity.