A computer system includes a server that issues an access request with a virtual volume among the plurality of virtual volumes allocated in a plurality of storage apparatuses as an access target and measures a latency in each access path connecting each storage apparatus and the server, and a plurality of control units which are disposed in each storage apparatus and control the I/O of data. Among the plurality of control units, a main control unit that controls the migration of a migration source virtual volume selects, as a migration destination storage apparatus, one storage apparatus connected to an access path from which was obtained a second measured value, which is a measured value that is smaller than a first measured value indicating a latency in an access path connecting a migration source storage apparatus, which includes the migration source virtual volume, and the server, and indicates a latency in an access path connecting a storage apparatus, other than the migration source storage apparatus, and the server, and allocates a migration destination virtual volume in the migration destination storage apparatus.