A storage management method, includes steps: detecting sizes of shared storage spaces of all terminal devices joined in a sharing system; dividing the all terminal devices into a number of device groups according to local area networks where the terminal devices located in; classifying the terminal devices of each group into a number of kinds of terminal devices according to the sizes of the shared storage spaces of the terminal devices; mapping the shared storage spaces of each kind of terminal devices of each device group to one corresponding virtual disk of one row of a virtual disk array card; and determining a size of a file to be stored when receiving a storing request, and selecting a virtual disk with size nearest to and greater than or equal to that of the file, and storing the file into the terminal devices mapping to the selected virtual disk.