A storage management device that manages a storage device including a plurality of volumes and executing data transmission and reception with respect to the storage units via one or more transmission resources in a plurality of transmission resources, the storage management device comprising: a memory that stores a procedure including executable instructions and a setting information of all of the volumes; a reception unit that receives an input of designation of a selection of some or all of the volumes and a type of a performance level for the volumes; a target value calculation unit that obtains a target value of performance set of data transmission and reception with respect to the selected volumes according to the input type of the performance level; a setting unit that registers, in the setting information, the obtained target value for the selected volumes; a monitoring unit that monitors a plurality of load of the one or more transmission resources and a plurality of measured values of performance of the selected volumes; and a bandwidth management unit that selects one resource having a highest busy ratio among the one or more transmission resources that are used by the selected one volume; that specifies sharing volumes which share the selected one resource; that selects a plurality of first volumes of which the target value is registered in the setting information from the sharing volumes; that reserves expansion or reduction of a bandwidth in the first volumes and second volumes of which the target values is not registered in the setting information among the sharing volumes based on a relation between the target value and the measured values; that obtains sum of tuning by adding a predetermined value in a case of an expansion reservation and subtracting the predetermined value in a case of a reduction reservation to an initial value, that decides a bandwidth allocation of the sharing volumes by determining expansion of the bandwidth when a sum result is a positive value and determines reduction of the bandwidth when the sum result is a negative value; and that instructs a bandwidth restriction unit of the storage device to tune the bandwidth using the decided bandwidth allocation. a memory that stores a procedure including executable instructions and a setting information of all of the volumes; a reception unit that receives an input of designation of a selection of some or all of the volumes and a type of a performance level for the volumes; a target value calculation unit that obtains a target value of performance set of data transmission and reception with respect to the selected volumes according to the input type of the performance level; a setting unit that registers, in the setting information, the obtained target value for the selected volumes; a monitoring unit that monitors a plurality of load of the one or more transmission resources and a plurality of measured values of performance of the selected volumes; and a bandwidth management unit that selects one resource having a highest busy ratio among the one or more transmission resources that are used by the selected one volume; that specifies sharing volumes which share the selected one resource; that selects a plurality of first volumes of which the target value is registered in the setting information from the sharing volumes; that reserves expansion or reduction of a bandwidth in the first volumes and second volumes of which the target values is not registered in the setting information among the sharing volumes based on a relation between the target value and the measured values; that obtains sum of tuning by adding a predetermined value in a case of an expansion reservation and subtracting the predetermined value in a case of a reduction reservation to an initial value, that decides a bandwidth allocation of the sharing volumes by determining expansion of the bandwidth when a sum result is a positive value and determines reduction of the bandwidth when the sum result is a negative value; and that instructs a bandwidth restriction unit of the storage device to tune the bandwidth using the decided bandwidth allocation.