China has now entered the pilot phase of the digital currency electronic payment, and the impact of the digital currency electronic payment on China's bank credit system is unknown. This paper analyzes the long-run equilibrium and short-run variation relationship between digital currency electronic payment and narrow money multiplier based on the long-run cointegration equation and short-run VECM using data from the first quarter of 2014 to the second quarter of 2022 for the scale of digital currency electronic payment usage and narrow money multiplier variables. It is found that the introduction of digital currency electronic payment will expand the narrow money multiplier by reducing the cash leakage rate and the excess reserve ratio, thus enhancing the credit creation capacity of China's banks; among the determinants of the narrow money multiplier, the proportion of factors that the central bank can control increases, and the central bank's monetary regulation capacity is enhanced. Finally, this paper proposes that the central bank should improve the technical construction of the central bank's digital currency, strengthen the cooperation with various participants, and enhance the supervision of merchant banks.