Objective: Research on Open Science practices in Health Psychology is lacking. This meta-research study aimed to identify research question priorities and obtain consensus on the Top 5 prioritised research questions for Open Science in Health Psychology. Methods and measures: An international Delphi consensus study was conducted. Twenty-three experts in Open Science and Health Psychology within the European Health Psychology Society (EHPS) suggested research question priorities to create a ‘long-list’ of items (Phase 1). Forty-three EHPS members rated the importance of these items, ranked their top five and suggested their own additional items (Phase 2). Twenty-four EHPS members received feedback on Phase 2 responses and then re-rated and re-ranked their top five research questions (Phase 3). Results: The top five ranked research question priorities were: 1. ‘To what extent are Open Science behaviours currently practised in Health Psychology?’, 2. ‘How can we maximise the usefulness of Open Data and Open Code resources?’, 3. ‘How can Open Data be increased within Health Psychology?’, 4. ‘What interventions are effective for increasing the adoption of Open Science in Health Psychology?’ and 5. ‘How can we increase free Open Access publishing in Health Psychology?’. Conclusion: Funding and resources should prioritise the research questions identified here. </p