This study attempted to find ways to recognize public libraries as social institutions with spatial functions to integrate generations for older adults in the face of Korea’s entry into a super-aged society. In particular, the goal of this study is to find out the implications and strategies for the design of libraries and facilities for older adults. And to this end, major guidelines related to senior citizens’ service spaces and facilities were analyzed to derive implications for senior citizens’ services. In addition, an in-depth interview survey was conducted on elderly users with experience in using library services to identify the priorities of creating spaces and facilities for the elderly. As a result, “Open elderly service space” and “Integrated elderly service space” were proposed as a way to organize the elderly service space in public libraries.