The European Union (EU) is adhering to decarbonization of its economy to tackle what is narrowly framed as ‘environmental issues’ of our socioecological and civilizational crises—including, but not limited to, climate change and biodiversity loss. A shift to bio-based economy (bioeconomy) is an important component of this effort. This paper applies theoretical ideas from decolonial environmental justice and degrowth, placed in the wider context of transformations, to analyse the EU bioeconomy policy within the global context, and to draw lessons and recommendations for just transformations in the EU bioeconomy policy. I identify five dominant logics and approaches in the EU bioeconomy that act as barriers for just transformations and propose alternative ones that can support such transformations. Barriers and alternatives include (1) framing ‘nature’ as a resource and service provider for humans, who are seen as separate from nature, and the need to abandon human–nature duality; (2) dominance of economic green growth and technoscientific policy solutions, and the need to place planetary justice at the centre of tackling socioecological crises; (3) a limited approach to justice, and the need to act upon climate and epistemic justice, including self-determination and self-governing authority; (4) the EU’s ambition for global leadership and competitiveness in global bioeconomic markets and governance, and the need to redefine global governance towards partnerships based on the principles of solidarity, mutual respect, reconciliation and redistribution of power and wealth; (5) hegemonic politico-economic structures and actor coalitions in charge of the EU bioeconomy, and the need for decentralized bottom-up leadership coalitions that promote direct democracy, local autonomy and sovereignty beyond state. I conclude with reflections on the politics of change and risks of co-optation, with a hope to inspire decolonial and just socioecological transformations in and beyond bioeconomy.