In recent years, adolescents face more and more challenges. Social changes increased the chance of being exposed to criminal risks, including adolescents’ drug abuse problem. The purpose of this study is to examine the correlations between drug use juvenile detainees and their mental health in correctional schools. Also to understand their characteristics from counselors’ observation, as well as the current counseling situation and dilemmas in correctional facilities. Mixed-methods research was used in this study, questionnaires included Resilience scale, DASS-21-C and drug use self-assessment scale. Data collection involving 78 adolescent in custody as participants in quantitative and a purposive sample of 18 professional counselors in qualitative research.

The result of Rogers’ regression analysis in quantitative data showed that by increasing on point of “self-awareness” variable may reduce the risk of mild depression by 66.7%, mild anxiety by 58.9%, and mild stress by 62.8%; increasing one point of “family bonds” variable may reduce the risk of mild stress by 87.6%. Quantitative analysis results showed that although drug use adolescents are extremely socialized, however, their internal mental status are extremely immature. They usually express negative emotions by violence, anger, and fighting. The final counseling goal in correctional schools is to build a successful transitional mechanism for adolescents’ reentry to the society. Counselors face many challenges such as not being able to establish good relationship with juvenile detainees due to the guidance or rules of correctional institutions.

Three themes suggestions emerged from this study:
(1) To prevent adolescents using drugs, parents should pay more attention to the family responsibilities. Also, the importance of youth mental health should be expanded.
(2) Drug prevention education needs to be present earlier in elementary school, enhanceing campaigns and propagandas are needed to keep up with modern teens.
(3) Correctional schools may conduct more communication and self-express lessons for juvenile detainees. Medical history information should also build up in a database to improve counseling efficiency.

Keywords: adolescents, mental health, juvenile detainees, drug abuse, drug harms