This study is set to examine the impact of corporate governance, firm attributes on financial Performance of selected commercial banks in Nigeria. The primary objective is to examine how corporate governance, firm attributes influence financial Performance of banks. In other to achieve the objective, secondary data were collected from the annual report of eleven banks (11). Data collected was analysed using panel regression. Based on the analysis the research found that there is no significant relationship between board size and firm performance (ROA), that there is no significant relationship between board independence and firm performance (ROA), also that there is no significant relationship between board gender diversity and firm performance (ROA), the study also reveals that there is no significant relationship between board meetings and firm performance (ROA), also that there is no significant relationship between director's shareholding, firm size and firm performance (ROA). However, based on the findings, the research recommended that board independence should be truly enhanced by appointing professional outside directors who are truly independent of the management and the activities of the firm, as this is the only way that the board can bring meaningful impact to bear on their monitoring role of management with purposeful objectivity and finally, optimal board size of six (6) based on our descriptive statistics results to banks in Nigeria. This supports the argument that spending on large board is a major decreasing factor to earnings and firm value.