Many children and adolescents have mental problems that undermine their normal development and functioning. It is estimated that about 10% of children and adolescents suffer from mental disorders at a sufficiently severe level to cause some degree of damage and require treatment.The aim of this paper is to determine whether there have been changes in the diagnostic categories in developmental psychiatry in children and adolescents treated at the Department for Children and Adolescent Psychiatry for the last fifteen years.The survey includes 844 patients treated at the Department for Child and Adolescent Psychiatry of University Clinical Center of the Republic of Srpska in the period from April 2002 to September 2017, involving only children and adolescents who were hospitalized for the first time. The sample consisted of 453 female subjects (54, 67%) and 391 male subjects (46, 33%). Subjects were divided into three groups: group 1 - hospitalization in the period from 2002 to 2007; group 2 - hospitalization in the period from 2008 to 2012; group 3 - hospitalization in the period from 2013 to September 2017.Female subjects accounted for more than half of the subjects within each group, with a mild increase in the number of patients in the last 4 years. In the overall sample, adolescents, aged 13 to 18 (51.66%) were the most frequent, with the lowest number of subjects under 6 years of age (3.91%). In the overall sample, the most frequent are: psychotic disorders in 18.60% of subjects; behavioral disorders and emotions in 17, 42% of subjects; suicide attempt, in 14.34% of subjects. By comparing data by groups, there has been a decline in psychotic disorders, and since 2008, adapting disorders and behavioral and emotional disorders have been most frequently diagnosed. There is an increase in the number of respondents who come from incomplete families in the last few years. About one-third of the sample (33.89%) were exposed to one or more types of abuse. 43.13% of children and adolescents with poor socio-economic status. Comorbid diseases are present in 5.92% of children and adolescents. In 26.18% of the sample, psychiatric disorders are present in the family history. The abuse of psychoactive substances was observed in 2.61% of adolescents, and this number has been increasing for the last five years. Family dysfunction is present in 57.35% of children and adolescents.In our study, there was an increase in the number of children and adolescents with behavioral disorders and adjustment disorders, as well as an increase in family dysfunctionality and psychoactive substances abuse in adolescents.