A method for refreshing a dynamic random access memory DRAM, comprising: generating a refresh command for a refresh unit in a DRAM, wherein the refresh command comprises a physical address of the refresh unit, and the refresh unit is storage space on which one time of refresh is performed in the DRAM; reading, from refresh data space, refresh information of the refresh unit according to the physical address of the refresh unit and by using a DRAM read command, wherein the refresh information of the refresh unit comprises a refresh cycle of the refresh unit; and performing a refresh operation on the refresh unit according to the refresh information; wherein the method further comprises: acquiring, from the refresh data space, refresh information of multiple successive refresh units that are after the refresh unit; receiving a refresh command for the multiple successive refresh units that are after the refresh unit; determining whether a quantity of refresh units, on which a refresh operation needs to be performed, in the multiple successive refresh units exceeds a threshold; performing a refresh operation of Auto Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed exceeds the threshold; or performing a refresh operation of RAS-Only Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed does not exceed the threshold. generating a refresh command for a refresh unit in a DRAM, wherein the refresh command comprises a physical address of the refresh unit, and the refresh unit is storage space on which one time of refresh is performed in the DRAM; reading, from refresh data space, refresh information of the refresh unit according to the physical address of the refresh unit and by using a DRAM read command, wherein the refresh information of the refresh unit comprises a refresh cycle of the refresh unit; and performing a refresh operation on the refresh unit according to the refresh information; wherein the method further comprises: acquiring, from the refresh data space, refresh information of multiple successive refresh units that are after the refresh unit; receiving a refresh command for the multiple successive refresh units that are after the refresh unit; determining whether a quantity of refresh units, on which a refresh operation needs to be performed, in the multiple successive refresh units exceeds a threshold; performing a refresh operation of Auto Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed exceeds the threshold; or performing a refresh operation of RAS-Only Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed does not exceed the threshold. acquiring, from the refresh data space, refresh information of multiple successive refresh units that are after the refresh unit; receiving a refresh command for the multiple successive refresh units that are after the refresh unit; determining whether a quantity of refresh units, on which a refresh operation needs to be performed, in the multiple successive refresh units exceeds a threshold; performing a refresh operation of Auto Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed exceeds the threshold; or performing a refresh operation of RAS-Only Refresh on the multiple successive refresh units when it is determined that the quantity of refresh units on which a refresh operation needs to be performed does not exceed the threshold.