The present invention provides a secure data storage and data access method and system, comprising data storage and data access. The data storage method comprises: a client acquires data that needs secure storage and acquires an executable file involving at least one encryption algorithm from a server; and the server selects one encryption algorithm from the executable file, and the client performs encryption and storage on the data that needs secure storage according to the encryption algorithm. The data access method comprises: the client acquires the data that is encrypted and stored and a decryption algorithm corresponding to the encryption algorithm selected when the data is stored; and the client decrypts the data that is encrypted and stored into a corresponding data type accoridng to the decryption algorithm, and thus the data leakage is effectively prevented.