With international diversification and domestic sustainable development, the uncertainty of economic policy becomes more prominent. It is of great research value to explore the influence of economic policy uncertainty on enterprise. This paper theoretically analyzes whether and how economic policy uncertainty impacts enterprise investment efficiency by constructing a stochastic optimal control model. Furthermore, this paper adopts the EPU index of China to empirically investigate the influence mechanism of economic policy uncertainty on the investment efficiency of enterprises. By exploring the actual effect and mechanism of economic policy uncertainty on enterprise investment efficiency, we find that economic policy uncertainty would induce enterprises' underinvestment or over-investment, thus weakening their investment efficiency. The main contribution of this paper is to combine economic policy uncertainty with the stochastic control theory model to analyze the influence of economic policy uncertainty on enterprise resource management. The conclusion provides a practical reference for enterprises to adjust investment strategies in the context of great changes in domestic and foreign economic policies.