Cases of excessive computer gaming are increasingly reported by practitioners in the psychiatric field. Since there is no standardized definition of this symptom complex, the aim of this study is to access excessive computer gaming in German adolescents as an addictive disorder and its potential negative consequences.Psychopathological computer gaming behavior was diagnosed by applying the adapted diagnostic criteria of substance-related-addictions as defined by the ICD-10. At the same time demographic variables, state of clinical anxiety and underlying cognitive mechanisms were analyzed.6.3 % of the 221 participating pupils - mostly boys with a low educational background - fulfilled the diagnostic criteria of a behavioral addiction. Clinically diagnosed adolescents exhibited limited cognitive flexibility and were identified to utilize computer gaming as a mood management strategy.These results can be interpreted as a first hint for a prevalence estimation of psychopathological computer gaming in German adolescents.