Background. Paroxetine has become an effectiveness treatment in anxiety disorders in adults. Despite the fact that this is an especially prevalent psychiatrist disorder in children and adolescents, there are very few studies in this population. This study examines the effectiveness of paroxetine in children and adolescents with anxiety disorders. Methodology. Fifteen children and adolescents with ICD-criteria for anxiety disorder were selected. Anxiety measurement was taken with STAI scale and was filled out before treatment and 6 months later (mean). We have used descriptive parameters and t Student test for the analysis of dependent samples. Statistic work was done with SPSS 8.0. Results. On first testing, the mean score for State Factor was 41.8 (ds: 5.9) and on second -after treatment- it was 24.66 (ds: 9.8). Trait Factor was 43.53 (ds: 8.27) on first testing and 25 (ds: 8.91) on second. These differences in mean scores for both State and Trait factors were significant (α=0.05, p