The study explores the financial stability of Omani Islamic banks and windows and identifies the impact of corporate governance mechanisms on them. Although the importance of the subject, there are a few research carried out on the influence of corporate governance mechanisms on Islamic banks’ stability operating in the Sultanate of Oman in particular. Therefore, the aim of the study is to fill up this gap by investigating the relationship of corporate governance mechanisms including Board of directors’ size (BODs), Board of director independence (BODI) and Shari’ah supervisory board size (SSBs) as independent variables with the financial stability of the banks in term of return on assets (ROA) and return on equity (ROE) as dependent variables. The study used banks’ age and size as control variables. The quantitative research method was used in this study, where secondary data, comprising the annual reports of two full-fledged Islamic banks and six windows operating in Oman, was used. In this study, we used SPSS and PLS applications to obtain quantitative measures of descriptive statistics, pair wise correlation and regression as a methodological tool to analyze the data. The findings of this study revealed that the corporate governance practices in the Islamic banks and windows in Oman have negative effects on their financial stability. In particular, the board of directors' independence and Shari’ ah supervisory board size and banks’ size have negative effects on the banks financial stability. However, in contrast, the board of directors’ size has positive significant effects on their financial stability. Actually, these findings cannot be generalized due to some limitations associated with size of sample, corporate governance variables, financial stability measurements used and other perspectives.