Modern slavery is a widespread issue that requires global cooperation to combat effectively. Despite increased awareness, finding solutions remains challenging, highlighting the need for ongoing collaboration and innovative strategies. This chapter aims to explore the relationship between human trafficking (modern-day slavery) and money laundering, to identify the root cause of modern slavery in Malaysia. The study employs a qualitative desk research methodology, primarily utilising an extensive literature review of both primary and secondary sources, to comprehensively analyse the complex relationship between modern slavery and money laundering in Malaysia, focusing on legal, social, and economic aspects. The preliminary findings showed that the relationship between human trafficking (modern slavery) and money laundering operates as a crime cycle, where illicit profits from trafficking are laundered to appear legitimate and then reinvested into further trafficking activities, perpetuating the cycle and highlighting their interconnectedness. The findings also indicated that to address the issue of modern slavery in Malaysia, it is essential to tackle the root cause: the continuous funding of these illicit activities by strengthening its Anti Money Laundering/Countering Financing Terrorism (AML/CFT) measures to combat money laundering. This paper would be beneficial for the AML legislative, policymakers and law enforcement agencies to develop more effective strategies aimed at addressing the interlinked challenges of modern slavery and money laundering in Malaysia.