An access system, an access device and an access method for accessing health information are disclosed. The access system includes a decentralized database for recording an authorization file corresponding to health information and a public key corresponding to the authorization file, a centralized database for using the public key corresponding to the authorization file to encrypt and store the health information corresponding to the authorization file into an access space, and an access device for issuing an access request of health information to the decentralized database based on user identification, for the decentralized database to identify and authorize the user identification based on the authorization file corresponding to the health information and ratify the access request and provide an instruction after identifying and authorizing the user identification, and for acquiring the encrypted health information from the access space based on the instruction.