Allowing patients to access their electronic health records (EHR) online, that we call the patient open- EHR, may help patients better understand and remember their health information, leading to improved health outcomes. In Japan, such solution is not yet widespread, and general patients' expectations for such solution are not known. The OpenNotes initiative in the United States of America (USA) had done various studies concerning the intervention of sharing doctors' notes, which are part of the EHR, with patients. Our study objective is to explore general patients' expectations toward potential benefits and risks of the patient open-EHR solution if given chance to use in Japan. A cross-sectional study was done using an online questionnaire. One hundred and eighty-three general patients without previous experience using the patient open-EHR service, responded to our survey after being recruited through SNS and posters at a university hospital not offering the solution. Comparison with the result of the OpenNotes original study, conducted in a similar setting, was also done. The results showed that participants were, similarly to the OpenNotes results, positive about the system's potential benefits; 90% agreed on the system ability to help them better understand their condition and remember their healthcare plan. On the other hand, they were much concerned about the potential risks especially privacy; 62% agreed they would be worried about their privacy. Adequate measures to provide highly secured systems and to allow patients to be better informed about the use of their personal health records should be taken to comfort future users.