The rising importance of market and operational risk to controlling financial risks inherent in Deposit Money Banks (DMBs) in Nigeria remains integral to their financial performances. Thus, this study assesses the impact of market and operational risk on DMB performance in Nigeria. Eight (8) years of data between 2015 and 2023 retrieved from the published annual reports of thirteen (13) DMBs were applied for this study. The analysis includes descriptive statistics and inferential statistics of correlation and panel regression for this study. The outcome of this study posits that the variables MRSK and OPSK have an impact of approximately 66%, 61%, and 65% on ROA for the pooled effect model, fixed effect model, and random effect model, respectively while their impact on EPS shows an impact of about 70%, 74% and 73% correspondingly for all the scenarios applied indicating that MRSK and OPSK are positive and negative predictors respectively. This study concluded that there has been a significant impact of both the MRSK and OPSK on EPS and ROA for the pooled, fixed and random effect model respectively for the period under review. This study recommended that management should prioritise implementing cost management measures to reduce the ratio of operating expenditures, which will ultimately result in improved profit margins. If the bank does not aggressively address recurrent modest losses in its daily operations, which are often caused by its inability to utilise its fixed costs effectively, its demise is inevitable.