The present invention relates to a data storage method, device and system and a management server. The data storage method includes: constituting a data pool from all of n data storage devices; when there is data for storage, polling all the devices in the data pool to select a group of m devices, and storing the data onto each of the selected group of m devices, where m is larger than one and smaller than n. The embodiments of the invention can address the problems of an existing data storage approach that a failing node causes an increased load on and instability of another node and that each node in the existing data storage approach has a low utilization ratio and poor predictability, so as to achieve uniform loads on the devices and high reliability of the nodes despite any failing node and improve the resource utilization ratio and predictability of the nodes.