The study investigated the creation and use of institutional repositories in selected tertiary institutions in south-east, Nigeria. The study was guided by two research questions. Descriptive survey research design was adopted for the study. The population of the study comprised all the academic staff of the selected tertiary institutions in the south-east, Nigeria. Multiple stage sampling procedure was used to draw 343 academic staff for the study. A researcher-developed instrument titled ‘‘Creation and Use of Institutional Repositories Questionnaire (CUIRQ)’’ was used for data collection. The instrument was duly validated by three experts and subjected to the test of internal consistency using Cronbach alpha which yielded an overall coefficient value of 0.82. The researchers together with two research assistants collected data for the study using direct administration. Out of 343 copies administered, 329 copies representing 96% were completed, retrieved and used for data analysis. Data were analyzed using mean and standard deviation. The results of the study revealed that institutional repositories are created and used in selected tertiary institutions in south-east. It was also found that. Based on the findings, it was recommended among others that the university management should organize institutional repositories-related conferences, workshops and seminars for the library staff to gain new insights and update their knowledge of creation of institutional repositories