The invention discloses an electronic medical record storage and sharing model and method based on the blockchains and solves problems of patient's rights of access to personal medical data and insecure storage and sharing of sensitive medical data in the prior art. The model is characterized by comprising data creators, data owners, cloud storage, federated blockchains and data consumers, whereinthe blockchain is a control center. The method comprises steps that system initialization is performed; medical data are acquired, and data storage with intercepted signatures is employed; data publishing with the improved DPOS consensus mechanism is employed; data sharing based on smart contracts is performed. The method is advantaged in that security, reliability, privacy protection and securestorage are achieved, in combination with the cloud storage technology and the interceptable signature technology, in the federated blockchains, users can set sharing conditions through the smart contracts, safe and effective data sharing and access can be realized, and strong practicality is achieved.