When library performance is regarded as service quality, competency in human resources should be considered as an influential factor. This study aims to identify relationships between job satisfaction of librarians and the service quality that users recognize in public libraries. Librarians and users in 10 public libraries in Seoul, Incheon, Gyeonggi province were sampled to measure job satisfaction and service quality with <TEX>$LibQUAL+^{TM}$</TEX> model. As a result, the higher the satisfaction of the duty itself and organizational factor show a high service quality. Consequently, to improve library customer satisfaction, the librarian's job satisfaction should be considered. Additionally, some practical implications are discussed.