This study aims to investigate the underlying causes of mental health crises among PDLs in New Bilibid Prison and establish a foundation for a comprehensive intervention program, recognizing the imperative need to address these issues. The research endeavors to propose evidence-based solutions that will enhance the overall effectiveness of the correctional system in promoting rehabilitation and reintegration by identifying key factors that contribute to psychological distress and assessing existing mental health services. This will improve the well-being of incarcerated individuals. This study employs a quantitative research design, specifically utilizing the descriptive survey method, to assess the causes of the mental health crisis among Persons Deprived of Liberty (PDLs) in New Bilibid Prison (NBP). It involves three groups of respondents: Persons Deprived of Liberty (PDLs), Custodial Officers, and Reformation Officers in New Bilibid Prison. Findings formulated after investigating the issue on the assessment on the causes of mental health crisis among Persons Deprived of Liberty in New Bilibid Prison in terms of Poor Living Conditions,Mental Health Services, Exposure to violence, Pre-Existing Psychological Disorder and Need for Family Visitation are Agreed. However, there are situations needed to improve. Based on the results, the study proposes to have a collaboration with external stakeholders that offers mental health programs and funding to help the PDL in preventing health crisis.