This degree project deals with electronic health record (EHR). The report is divided into two main sections; literature study on electronic health record and an EHR system implementation. In the literature study section, EHR background, development history and service condition are introduced. The paper focuses on the sharing of medical information in different users, data safety and privacy. The adjunctions of computer science, technologies are used to solve the medical informatics’ problems. In the implementation section, based on the study of the current EHR systems, the design and implement of a shared EHR system are presented, which can be accessed by different doctors and patients. Access control function and cryptography protections are included in this system. The system test and evaluation are also given.