OBJECTIVE:To integrate the findings of research on electronic personal health records (e-PHRs) for an understanding of their health literacy demands on both patients and providers. METHODS:We sought peer-reviewed primary research in English addressing the health literacy demands of e-PHRs that are online and allow patients any degree of control or input to the record. A synthesis of three theoretical models was used to frame the analysis of 24 studies. RESULTS:e-PHRs pose a wide range of health literacy demands on both patients and health service providers. Patient participation in e-PHRs relies not only on their level of education and computer literacy, and attitudes to sharing health information, but also upon their executive function, verbal expression, and understanding of spoken and written language. CONCLUSION:The multiple health literacy demands of e-PHRs must be considered when implementing population-wide initiatives for storing and sharing health information using these systems. PRACTICE IMPLICATIONS:The health literacy demands of e-PHRs are high and could potentially exclude many patients unless strategies are adopted to support their use of these systems. Developing strategies for all patients to meet or reduce the high health literacy demands of e-PHRs will be important in population-wide implementation.