A rights objects acquisition method of a mobile terminal in a digital right management system is provided for acquiring multiple rights objects in a composite manner. An objects right acquisition method of a mobile terminal may include generating, in response to a group rights object (RO) acquisition command, a group rights object acquisition request with content identifiers assigned to individual contents corresponding to the rights objects indicated by the group rights object acquisition command, sending the group rights object acquisition request to a rights issuer; and receiving an group rights object acquisition response containing rights object identifiers assigned to the rights objects from the rights issuer. The present invention streamlines the RO acquisition process, especially when acquiring multiple ROs.