Good corporate governance is perceived as a key component of sustainability for Microfinance ‎Banks (MFBs) as it is assumed to help them achieve their social and financial objectives. This study ‎examined the effect of corporate governance on the performance of MFBs in Nigeria. Corporate ‎governance was proxied by audit committees, board size and composition while Return on Equity ‎‎(ROE) was used as the measure of financial performance. Twelve MFBs were randomly selected ‎from South West, Nigeria. Secondary data was obtained from the annually published reports of the ‎selected licensed microfinance banks in Nigeria between ten years period of 2011 and 2020. Data ‎were analyzed using regression and correlation techniques.‎ The results demonstrated that board size correlates favourably and significantly with MFBs ‎performance, implying that larger boards improve bank performance. Board composition exhibited ‎a strong positive relationship with MFBs’ performance. Furthermore, audit committees correlate ‎positively and significantly with MFBs’ performance, demonstrating that audit committees are ‎important components of corporate governance. Finally, the study found that corporate governance ‎proxies (audit committees, board size, and composition) have a positive and significant effect on ‎MFB's performance in Nigeria.‎ Consequentially, this study suggests that an operational audit committee be established if MFBs’ ‎credibility, efficiency, competitiveness, and sustainability are to be ensured. MFBs should also ‎maintain a completely unbiased board composition to ensure optimal achievement of goals and ‎long-term profit maximization.‎