Objective: To study the rate of, and factors associated with, recognition of psychiatric disorders and self-perceived problems among 18-year-old adolescent boys. Method: The study population consisted of 2347 Finnish boys born during 1981 attending military call-up (79.7% of the original sample). At age 8, the boys were evaluated by parental and teacher Rutter scales and by self-reports using the Child Depression Inventory (CDI). At military call-up 10 years later, the boys filled in the Young Adult Self-Report (YASR). Information about psychiatric disorders recognized at the military call-up health examination was obtained from the national military register. Results: About 4.6% of boys were recognized as having a psychiatric disorder at the military call-up medical examination. In addition, 23.1% of boys reported emotional, behavioral or relational difficulties but were not recognized as having an ICD 10 psychiatric diagnosis at the military call-up medical examination. A higher level of psychopathology, problems across different life domains and early onset of problems were more strongly associated with recognition of psychiatric disorder than with self-reports of difficulties without a recognized psychiatric disorder. All informant sources, parents, teachers and children themselves at age 8, independently predicted recognition of psychiatric disorders and perceived difficulties 10 years later. Conclusions: Only a minority of adolescents with psychiatric problems are recognized as having a psychiatric disorder in the health services. Efforts to prevent psychiatric disturbance in early life are emphasized. The use of screening methods in school health settings to detect children in need of child mental health services is justified.