School life has a wide impact on social and psychological adjustment of the child and we adolescent so that lack of feeling of support and acceptance , rejection from classmates ,verbal and physical aggression can be related to low self-esteem. Violence among students is a growing problem in recent years. In the present study we were interested to explore school bullying as a form of violence in middle schools and its relationship with self-esteem of bullied students. We were also interested to know more about types of school bullying, where it occurs and its negative psychological effects on social adjustment of bullied students. The findings are based on a random sample of 490 students from the public middle school of Algiers(west area ) during the school year 2006/2007 .They were asked to respond to \"shortened bullying questionnaire\"( Dan Olweus) and \"self-esteem\" (Rosenberg) scales. The results obtained from analysis of data showed that school bullying is wide spread among middle school students at different scales . - Students were bullied at least once or twice during the school year. - Students who were victims of bullying had lower scores in self-esteem scale than students who had never been bullied by peers. - Students bullied more than once or twice about once a week or several times a week had lower self-esteem than students bullied only once or twice. Results finally stressed the importance of self esteem as an important part of psychological health in adolescence so it is necessary to support and help the victims of school bullying by planning strategies to prevent bullying in the school environment . Results were interpreted and implications for counseling were suggested.