In this paper, we designed a role-based emergency medical information security system REMISS added the security concept to the existing emergency medical information system. Also we suggested a REMISS protocol based on HL7 for using the emergency medical information and the security information. The procedure of security consists of user authentication phase and role/permission assign phase in the REMISS. The REMISS can supply proper security service since the REMISS assign proper permissions to each users of emergency medical information system and allow the user to access the permitted emergency medical information by using security information of the REMISS. There are some advantages that REMISS can adapt to the changing of the role of each user by dynamic exchanging the security information and assigning permissions to each user.