This study sought to analyse the effect of internal control mechanism on institutional performance at the Sunyani Technical University (STU). The study adopted quantitative research approach and also used the descriptive survey design. The target population for this present study comprised staff and management of STU. They included staff and management excluding junior staff (auxiliary staff – security, cleaners and casual workers). Convenience sampling technique was employed to select 184 respondents from STU. Pearson’s linear regression analysis model was used to analyse the relationship between internal control systems and business performance. The study revealed positive relationship between the asset controls, and procurement controls and institutional performance. The positive relationship between them was significant and therefore supported the state hypothesis. Again, it was revealed that between the cash controls, payroll controls and institutional performance, there exists a positive relationship between them and it was significant and therefore supported the stated hypothesis.