The institutional repository is a major means of providing open access to academic output and is changing academic communications. As use of the institutional repository is spreading, research advancing its management policy and technology has been conducted in the library and academic communities. This study has undertaken a co-word analysis of author keywords in articles from the SCOPUS database from 1997 to 2012 and found 8 clusters that represent the intellectual structure of Institutional Repository Research, including ‘Metadata’, ‘Open Access’, ‘Institutional Repository’, ‘digital Library’, ‘dSpace’, ‘Copyright’, ‘Preservation’ and ‘Sematic Web’. To understand these intellectual structures, this study used a co-occurrence matrix based on Pearson’s correlation coefficient to create a clustering of the words using the hierarchical clustering technique. To visualize these intellectual structures, this study carried out a multidimensional scaling analysis, to which a PROXCAL algorithm was applied.