Juvenile delinquency is a complex socio-economic problem that has a negative impact on all members and processes of a social structure and their economy. This study was conducted to assess the main causes and effects of juvenile delinquency in Belay Zeleke and Atsie Tewodros Sub-cities of Bahir Dar City Administration. The study has applied both quantitative and qualitative research methodologies. The purposive sampling method was used to select the police station heads and focus group discussion participants, whereas a simple random sampling technique was used to select juvenile delinquents, police officers & department heads, and the conflict resolution committees. The primary data were collected using questionnaires, focus group discussions, and interview methods, whereas the secondary data were collected from both published and unpublished documents. The data collected with the questionnaires were analyzed using thematic analysis and using SPSS V25 with descriptive statistics. At the same time, the data collected with the interview and focus group discussion method was analyzed using the thematic (qualitative) analysis method. According to the study results, personal factors like behavioral or non-behavioral, social factors like family cases, community influences, and economic issues like un employment, and poverty are identified as the major causes of juvenile delinquency. The findings of the study also indicated that juvenile delinquents are aggravating security threats, by causing family instability, social disintegration, economic crises, and political unrest. Not only that but also the findings reveal that juvenile delinquency cases are affecting both regional and national economies through these negative impacts on the tourism and investment industries. To conclude, the research assessed the most common causes and effects of juvenile delinquency in those sub-cities of Bahir Dar City Administration on security concerns. Based on the findings, juvenile delinquency is now aggravated and it is one of the main security threats in the city. The study recommended that the government and other concerned bodies should implement the recommended strategies in this research to minimize juvenile delinquency. There should be strong cooperation among police officers, the community, religious, and civil society organizations to reduce the effects of juvenile delinquency