Abstract: With the vigorous development of the digital industry and the need for payment efficiency and security, the issuance of central bank digital currencies (CBDC)is gradually approaching. Theoretical analysis shows that under the current issuance framework that China may choose, CBDC will reduce the amount of currency, increase reserves, currency multiplier, money supply and the volatility,which will reduce bank system stability. At the same time, combining the Lucas currency business cycle model with the AD-AS model to discuss the impact on economic growth, we believe that the issuance of CBDC as an unpredictable monetary policy will have a positive impact on the economic growth in the short term, but this promotion effect will disappear in the long run. The simulation prediction results of the PSO-BP neural network model are basically consistent with the theoretical analysis, which show that the impact of issuing central bank digital currencies on the stability of China′s banking system is negative and controllable, and the overall effect on economic growth is positive in the short term. Further robustness tests confirmed the reliability of the prediction results.

Key words: central bank digital currency, bank stability, economic growth, PSO-BP neural network