This study examined the comparative comparison of leadership styles and work performance among university librarians in Osun State, Nigeria. The research utilized a descriptive survey research design. The survey encompassed a total population of 151 librarians. The whole enumeration sampling strategy was used to get all the university librarians. An customized questionnaire was used to gather data. Three library and information science specialists checked the device to make sure it was accurate. Fifty librarians from the institution who were not part of the study were used to test the instrument's reliability. Using the Cronbach Alpha technique, we found that the scores from the trial tests had an alpha coefficient of 0.78. The data acquired were analyzed using frequency count, percentage, mean, and standard deviation. A multiple regression analysis was performed to evaluate the null hypothesis at a 0.05 level of significance. The results showed that the job performance of university librarians in Osun State, Nigeria was average, with a mean score of 663.7. In university libraries in Osun State, Nigeria, there are four main types of leadership styles: democratic, charismatic, autocratic, and bureaucratic. There existed a tenuous and adverse correlation between leadership style and work performance among librarians (r = -0.037; p < 0.05). The research determined that leadership style significantly influences work performance among university librarians in Osun State, Nigeria. The report also suggested that university librarians should be fully involved in the accreditation process for university courses, among other thing. Keywords: University Librarians, Job performance, Leadership style, Comparative assessment,