This study investigated the effect of employee relations on performance of selected tertiary institutions in the Sunyani Municipality. Using quantitative research design, questionnaires were administered to 264 regular staffs of three selected tertiary institutions. Descriptive statistical tools (Frequency, percentage) as well as inferential statistics (Simple regression, Pearson’s correlation coefficient and Cronbach alpha) were used with the help of Stata version 13. Furthermore, the study revealed a positive and significant relationship between respectively, conflict resolution and organizational performance (r =.656, n=183, sig value < .000); employee empowerment and organizational performance (r = .727, n = 183, sig value < .000); employee compensation and organizational performance (r = .416, n = 183, sig value < .000); and employee voice and organizational performance (r = .440, n = 183, sig value < .000) in tertiary institutions. More importantly, employee relations management had a strong and positive correlation with organizational performance. The study concluded that employee relations management is vital to the success of any company or organization. It is recommended that future research extends the population to cover tertiary institutions across all the 16 regions so as to establish the general situation of employee relations in tertiary institutions in Ghana. Also, mixed-method approach is recommended for future research in order to better explain the entire phenomenon in details.