<p>The transformation of the energy system towards climate neutrality poses countries in Central Europe with complex multidimensional challenges. Green hydrogen is seen as a key technology for enabling cross-sector coupling and decarbonising CO₂-intensive sectors such as industry and mobility. In this context, this study identifies and analyses relevant stakeholders in eight countries of the Danube region as part of a transnational cooperation. A systematic stakeholder analysis is used to identify 45 stakeholders in six stakeholder groups and evaluate them in terms of their perceived importance, influence and attitude towards the development of green hydrogen ecosystems. The stakeholder mapping shows country-specific differences and overarching patterns in the prioritisation of political, economic and civil society actors. Political institutions and key economic players such as energy suppliers and industrial companies are particularly influential. At the same time, stakeholders with a focus on fossil energies show ambivalent attitudes, pointing to possible transformation conflicts. Thus, the analysis provides empirically sound findings for the design of targeted participation strategies and governance-orientated policy design in European hydrogen policy.</p><p></p>