Knowledge is the real and necessary requirement of today's societies, and we benefit from information and knowledge in our lives and promote our health through it. Health is a category that is important in life and several factors can affect its formation, sustainability and promotion. Libraries, and librarians as facilitators of knowledge dissemination, can promote social health through managing and transforming knowledge into wisdom, providing intellectuality, and internalizing knowledge in human and throughout the community. The purpose of this study was to explain the rational use of libraries as the main causes of social health by using a qualitative method and resorting to grounded theory approach. Participants in this study were 22 educated people at least with PhD degree, which were considered to be rich in information on the research subject. The participants were selected by purposeful sampling method. The data were collected using semi-structured interviews while the interviews were ended in saturation phase or in the theoretical adequacy. Data analysis was performed using the Strauss and Corbin method or three stages of open, axial, and selective coding. After analyzing data, 300 initial open codes, about 100 merged codes, 20 sub-sub categories, 9 sub-categories, and 3 main categories were appeared. The main category was “The wisely services of libraries as the predisposing factors of social health." The findings showed that libraries can play an effective role in the formation and promotion of social health using their resources and librarians’ capabilities.