Research decisions should be informed by an understanding of the state of knowledge and stakeholder perspectives. We used knowledge synthesis and exchange to define priorities for prison health research in Canada, including a systematic review of interventions, a scoping review of prison health research in Canada, a narrative review on the health status of prisoners in Canada, and a Delphi process. We defined gaps in knowledge about health status and interventions, identified promising interventions, and achieved consensus regarding priorities for research. These systematic processes provide a strong evidence base and justification for future research in prison health in Canada. We hope these data will influence decisions regarding prison health research, coalesce the community of prison health researchers, and galvanize this area of research.