Medical information is used in various fields such as medical technology development, improvement of medical service, medical dispute, but it does not yet fully meet security requirements. In order to improve the medical information environment, we investigated incidents, medical disputes, and summarized current medical information utilization status. And we parsed the security requirements presented by medical information standard like HL7 or DICOM. As a result, it has been confirmed that medical information want security requirement such as reliability, confidentiality and integrity, usability, non-repudiation, audit, authority management, and authentication. In this paper, we propose medical information sharing service architecture based on bockchain and framework for it s implementation, that can satisfy the reliability, integrity, auditability and usability of medical information security. As a result of applying the simulation technique, it was confirmed that the proposed architecture and framework can satisfy the target security requirements for the medical information. However, it needs additional satisfaction for confidentiality and security requirements for access control, authentication, and auditing.