In this study, as examples of domestic libraries currently using the cloud-based library system, the main characteristics and issues that appeared in the experience of use divided into the processes of introduction, conversion, and operation of each system were investigated, and the results are as follows. First, it is said that new systems were introduced as alternatives to problems caused by the operation of the existing system, and the current products were selected because they were cost-effective. Second, the main issues in the conversion process were data migration work, implementation of existing service functions, and linking problems of internal and external systems in the library. Third, the main advantages identified in the operation process were cost reduction, simple installation and automatic management and maintenance, and convenient use in mobile devices. The main drawbacks were the difficulty of customizing that reflects the characteristics of the library, and the need for stability of the network. The disappeared role of the information technology librarian is the regular system inspection and maintenance support, and various new roles have been suggested. The responses of librarians and users to the new system were generally satisfied rather than dissatisfied.