The results revealed an overrepresentation of immigrants, high levels of psychosocial adversity (large family size, low parental educational level, poverty, and family offending history) and high prevalence rates not only of externalizing disorders, such as conduct disorder, but also internalizing disorders, including anxiety and depression problems. It is concluded that young males in Greek correctional institutions need support at many levels, and especially for mental health problems. In Greece, a factor that has been related to juvenile delinquency in recent years is immigrant status. Over the last decade, Greece has received growing numbers of immigrants, 65 percent of whom were Albanians. Also, in Greece, an increase in the number of young offenders referred to psychiatric services has also been reported. The aim of this study was three-fold: (1) to describe the demographic and family characteristics of young males held in the Greek juvenile justice system, (2) to determine the prevalence of mental health problems of this population, and (3) to compare Greek and immigrant young males on the above variables. The study consisted of 93 young males, randomly selected from the 3 main juvenile detention facilities in Greece who completed the Greek version of the Youth Self Report (YSR). Tables and references