Purpose - The purpose of this systematic review is to synthesize existing empirical research on the psychological burden of financial obligations, specifically examining the impact of debt and financial stress on mental health (MH) across diverse populations and contexts. Design/methodology/approach - Using Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, this paper analyzed 66 peer-reviewed articles from Web of Science (2003-2024) via bibliometric and theory-context-characteristics-methodology frameworks. The search equation combined terms like debt, indebtedness (ID) and mental health (MH). Findings - Debt consistently correlates with adverse MH outcomes (depression, anxiety, suicidality), mediated by factors like perceived control and social support. Longitudinal studies reveal enduring "scar effects" of financial crises (e.g. 2008 recession, COVID-19). Vulnerable groups (low-income families, minorities, youth) face heightened risks, while systemic factors (policy gaps, labor instability) exacerbate stress. Methodologies are predominantly quantitative (national surveys and longitudinal panels), with emerging use of big data (e.g. social media analysis). Originality/value - This review integrates fragmented literature, highlighting debt as a critical social determinant of MH. It calls for interdisciplinary frameworks linking individual coping with structural interventions (e.g. debt relief policies and community resilience programs). Gaps include limited low and middle income countries representation and policy evaluation studies. Future research should prioritize intersectional analyses and longitudinal designs to inform equitable mental health and economic policies.