Circular economy (CE) offers a solution to the developing nations' growing food waste problem, yet implementation remains limited. This study explores CE adoption across agri-food supply chains through a multi-stakeholder analysis, considering both agri-food suppliers and consumers in Sri Lanka to identify context-specific barriers and enhance waste reduction and resource circulation. Utilizing a quantitative approach, the research applies partial least squares structural equation modeling (PLS-SEM) to validate barriers identified in prior literature. Drawing on four theoretical perspectives: Resource Dependence Theory, Contingency Theory, Institutional Theory, and Stakeholder Theory, a conceptual framework is developed to analyze how these barriers affect CE adoption in the agri-food supply chain. Accordingly, this study identifies four key barriers to CE adoption in sustainable agri-food supply chains: Environmental Laws and Policies (ELP), Market Acceptance (MA), Supply Chain Actors’ Coordination (CSA), and Short-term Economic Benefits (SEB). MA and ELP were most influential for suppliers, while consumers emphasized ELP and CSA. Lifestyle showed significant moderation effects in consumer and combined datasets, whereas Environmental Conditions observed no significant moderation. The study contributes by bridging theoretical gaps on CE barriers through multiple organizational lenses and by offering practical insights into CE adoption within developing economies.