<p>Plastic pollution presents a significant and rising challenge for Southeast Asia, driven by rapid economic growth, urbanization, and changing consumption habits. This study aims to examine the political and socio-cultural factors that influence the success of plastic waste bans in selected Southeast Asian countries, including the Philippines, Indonesia, Malaysia, Thailand, and Vietnam. Using a qualitative comparative approach, the paper combines policy analysis and literature review to explore the design and implementation of plastic ban policies, public perceptions and behavioral responses, and the unintended consequences of these measures. The results show that although regional and national governments have introduced increasingly ambitious plastic regulations, their practical effectiveness remains limited due to fragmented governance, infrastructure gaps, and socioeconomic inequalities, especially impacting the informal waste sector. Public awareness is high, but behavioral change is inconsistent, limited by access to affordable alternatives. Additionally, substitution effects, policy gaps, and social equity issues have created new environmental and economic challenges. The paper concludes with strategic recommendations for enhancing policy outcomes, including harmonized regulations, infrastructure improvements, inclusive stakeholder engagement, and regional cooperation toward sustainable, equitable plastic waste management governance.</p>