In this volume migration method, a migration-source P-VOL and a migration-destination S-VOL forming a volume pair in a migration-source storage system are migrated to a migration-destination storage system uninterruptedly. First, a logical volume (migration-destination P-VOL), in which the storage area of the migration-source P-VOL in the migration-source storage system is mapped, and a migration-destination S-VOL, which becomes a replicated volume of the logical volume, are created. The migration-destination storage system attaches, to the migration-destination P-VOL and the migration-destination S-VOL, the same identifier as the identifier that the migration-source P-VOL and the migration-source S-VOL have, causing a host computer to recognize that the migration-destination P-VOL and the migration-destination S-VOL are the same volumes as the migration-source P-VOL and the migration-source S-VOL. Subsequently, an access path from the host computer to the migration-source P-VOL is switched to the migration-d
