Corporate disclosure is a key mechanism of corporate governance. This study examined the effect of corporate governance disclosure (CGD) on the financial performance of commercial banks listed on the Nigeria Stock Exchange. Based on the provisions of the Code of Corporate Governance for Public Companies in Nigeria, 2011 and the Code of Corporate Governance for Banks and Discount Houses 2014, the study developed a disclosure checklist and employed content analysis technique to extract corporate governance (CG) from 78 annual reports of 13 Nigerian commercial banks from 2011 to 2016. The study trichotomized CGD into those relating to the board of directors, risk framework, and whistleblowing policy. The results of the hypothesized relationships showed a positive and significant association between CGD and the banks' financial performance, with a positive effect of CGD on the board of directors and whistleblowing policy. However, the study did not find a significant association between CGD of risk management framework and the banks' financial performance. This study contributes to the body of knowledge by providing a broader understanding of the effect of CGD on banks' financial performance. The development of a disclosure checklist based on the regulators’ codes of corporate governance is a useful addition to the literature.