Introduction/Objectives: Social prescribing aims to improve health and well-being by connecting individuals with mental health, housing, and loneliness issues to informal services and support. This approach connects individuals to activities and services in their community to fulfill their practical, social, and emotional needs. However, no reports of community libraries being prescribed as a place to be referred through social prescribing were observed in the literature and the impact of community libraries on community residents and communities in social prescribing. The aim of this study was to identify the functions of a community library operated by medical and social professionals in the social prescribing initiative, its functions, and its impact on community residents and communities. Methods: Semi-structured interviews were conducted with the users of the Daikai Bunko Library, a community library in Toyooka City, Japan. The library was established by a primary care physician and community residents as a place where visitors can stay and use it as a library, a bookstore, a café, and a consultation place. Interviews were recorded, and the verbatim transcript was analyzed using the Steps for Coding and Theorization. Results: Ten individuals participated. The theoretical description of the interview texts revealed 11 categories as the function of the library and its effect on the individuals and the community: a place to stay, attractive space design, diverse accessibility, choosability of various roles, consultation function, social support, empowerment, mutual trust, formation of connections across generations/attributes, co-creation, and social impact. Conclusions: We found that a community library run by medical and social professionals was a useful social prescribing site and had various effects on the community residents who used it. Various functions of the community library, such as consultation functions and attractive space design, may lead to effects on local individuals providing social support and empowerment, with social impacts such as co-creation and formation of connections to the local community.