This study aimed to analyze the intellectual structure of university library research by complementarily utilizing co-citation analysis and direct citation analysis. The study analyzed 627 papers published since 2002 related to university libraries and their references retrieved from the Korea Citation Index (KCI) database. Co-citation analysis revealed 15 major research topic subclusters, which were further categorized into seven main areas: library space, systems, users/usage, service quality, online services, specialized services, and planning/evaluation. Analysis of temporal changes in research topics confirmed a significant shift in university library research themes around 2012-2013. Direct citation analysis uncovered six additional research topics not identified in the co-citation analysis: organizational management, electronic scholarly information, user studies, next-generation digital libraries, efficiency analysis, and cooperative storage facilities. This study demonstrated the effectiveness of complementary use of co-citation and direct citation analyses in examining intellectual structures.