To evaluate how the deposition of journal articles in Institutional Repositories(IRs) affects the number of citations and e-journal usage, we placed some articlespublished in Zoological Science in two IRs, and compared their use in IRswith e-journals, as well as with the number of resulting citations between 2008and 2009. The results reveal that deposit in IRs did not reduce e-journal usage.Moreover, whereas the journals gained new readers, this did not have an effecton the number of citations.