This paper analyzes the dual effects of policy support on “subjective investment intention” and “objective investment opportunity” by constructing Difference-in-Difference and intermediary effect test based on the change of the “Five Year Plan” and how they resonantly further influence the micro logic of enterprise financial asset allocation. The study finds that industrial policy support has a significant role in promoting the allocation of corporate financial assets. On the one hand, industrial policy support can not only enhance the enterprise's investment willingness through the mitigation effect of financing constraints, but also improve the enterprise's risk tolerance and strengthen the risk bearing through the sheltering effect, so as to further enhance the “subjective investment intention”. On the other hand, the investment surge caused by policy support will worsen market competition, policy foresight and social value, and inhibit the shortterm economic value of enterprises, which will lead to the decline of “objective investment opportunities”. Finally, under the resonance effect of increasing objective investment uncertainty and increasing subjective investment willingness, enterprises choose to invest in alternative financial assets. In terms of heterogeneity, the enterprises with higher investment opportunity, better operating income and higher risk of main business have weaker willingness to increase financial assets investment, which indicates that enterprises' allocation of financial assets is more like icing on the cake, rather than fundamentally “turning from real to virtual”.