Internal audit has been in increasing demand in both the public and private sectors because it has impacted a lot by instituting several rules and control measures to guide their operations, especially in tertiary and second-cycle institutions. The main purpose of the research was to assess the impact of the internal audit system on good corporate governance through a study of tertiary and second-cycle institutions in Wa, Upper West Region of Ghana. The main objective of the study is to assess the impact of the internal audit system on corporate governance. Nonrandom (purposive) and random sampling techniques were employed in the study. The population was internal auditors and management at four tertiary institutions and one municipal education office, making a total population of 5. The sample size was made up of 10 respondents, consisting of 5 internal auditors and 5 management staff. The study revealed that internal audit activities help promote good corporate governance by focusing on compliance with laws and regulations and also evaluating fraud and errors. Also, the study found that the internal auditors play a key role in their institutions, and most of these institutions have inadequate audit staff. It is recommended that the internal audit units be provided with enough staff in order to be able to do their work effectively and on time. Internal auditors need to be adequately resourced, especially in the use of appropriate technology, rather than focusing too much on traditional systems.