Audit fees and audit tenure are critical factors in the auditing process, particularly in the banking sector where financial performance is closely scrutinized. Investigating how these factors interact with financial performance can provide valuable insights. This study examined the moderating role of audit tenure in the relationship between audit fees and the financial performance of the Deposit Money Banks (DMBs) in Nigeria listed on the Nigeria Exchange Group from 2012 to 2021. The study explored secondary data that is sourced from the audited annual reports and accounts of the selected DMBs. A purposive sampling technique was used to choose 12 DMBs whose stocks were actively traded on the stock market during the sample period and for which necessary information was readily available. In analyzing the data, the study explored multiple regression analysis by using Return on Asset as the dependent variable; Audit Fee as the independent variable; Audit Tenure as the moderating variable, and Firm Size, Firm Age, and Leverage as the control variables. The result showed that the Firm Size and Interaction of Audit Fee and Audit Tenure had a positive and significant effect on financial performance while Audit Fee, Audit Tenure, Firm Age, and Leverage had a negative and significant effect on financial performance. The result concluded that audit tenure, audit fees, and their interactions have a significant effect on the financial performance of the DMB. The study therefore recommended that the Nigerian banking industry should develop strategies for managing audit relationships over the long term while ensuring the effectiveness and integrity of the audit process. This study contributes to the understanding of audit dynamics within the banking sector, highlighting the relationship between audit fees, audit tenure, and financial performance. By demonstrating the moderating effect of audit tenure on this relationship, it emphasizes the importance of long-term audit relationships in enhancing the effectiveness and integrity of the auditing process, providing valuable insights for regulatory bodies and banking institutions alike.