The invention belongs to the technical field of medical data management, and relates to a medical record storage, sharing and security claim settlement model and method based on a block chain. Firstly, credible sharing of medical data of patients among medical institutions is achieved through the blockchain technology, and a lifelong medical record is established for the patients; based on a Hashchain type storage structure, the medical data cannot be tampered; secondly, an improved CP-ABE-based cryptographic primitive SHDPCPC-CP-ABE is proposed, security encryption and fine-grained access control on the medical data are realized, and a patient can conveniently and efficiently access and authorize a medical institution to read the medical data; and finally, a Paillier homomorphic encryption technology is utilized to realize safe medical insurance claim settlement, and the privacy of the patient is protected when the patient interacts with a third-party non-medical institution. According to the invention, security, confidentiality, reliability and integrity of medical data can be realized, and confidential sharing of private data is supported.