Abstract

 Universities worldwide had been ranked based basically on their presence on the world wide web- Webometrics and Academic Ranking of World Universities- AR WU. Nigeria with higher number of universities in Sub- Saharan Africa viz a viz large volume of research output and scholarly publications is not very visible in this world ranking of universities. This may be attributed to the low level of open access institutional repositories in the universities. This study was therefore designed to investigate open access institutional repositories and academic visibility of Nigerian Universities. The study adopted Survey research design. The population of the study consists of all the 126 u11iversities in Nigeria (public and private. A sample size of26 respondents, made up of 13 university librarians and I 3 librarians in charge of JCT in the university libraries were purposively selected for the study. Findings revealed that only I 3 universities in Nigeria have established functional open access institutional repositories; in the ranking of Nigerian universities in 201 6, UNN ranked 1433 in the world and first in Nigeria; types of digital contents in the I Rs; identified factors militating against the establishment/functionality of institutional repositories. The study made suggestions for possible solution to the challenges such as improvement of ICT infrastructure in the universities and advocacy among others. Key words: Open Access, Institutional repositories, visibility, Nigerian universities, ranking