A cloud storage data access method, apparatus and system are provided to enhance data availability and fault tolerance of cloud storage. In accordance with the present application, data redundancy at a cloud storage data center level is created by creating parity values of original data to be stored through parity calculation on a data transmitting end and placing the original data, its parity values and the data used to create the original data parity values in different cloud storage data centers, according to a predetermined data redundant storing rule.