The study examined the effect of decentralized index and immutable ledger on the level of performance of deposit money bank in Nigeria. The survey research design was used and the main data collection instrument was the structured questionnaire which was administered to employees in four (4) selected deposit money banks in Delta State (Ecobank, Fidelity Bank, Zenith Bank and United Bank for Africa). A sample of ninety (90) respondents was used and data gathered were analyzed using descriptive statistics (standard deviation, frequency count, and simple percentage) and inferential statistics (regression analysis). Findings indicated that there is a positive effect of decentralized index and immutable ledger had significant effect on the level of performance of deposit money banks. Based on the findings, it recommends that deposit money banks should leverage decentralized index to increase efficiency, reduce costs, and enhance customers’ satisfaction. Also, policymakers should create enabling environment for the continuous use of immutable ledger. While acknowledging the vital role decentralized index and immutable ledger can play in enhancing performance, there are challenges such as regulatory uncertainty, security risks, and scalability issues, hence management of deposit money banks should develop strategies to address these challenges associated with the use of decentralized index and immutable ledger. JEL Classification: M12; M15