Fintech plays a crucial role in promoting the flow of financial vitality into key areas and weak links of the real economy, and in improving the inclusiveness and resilience of finance. Fintech is a booster that empowers the high-quality development of the real economy and optimizes the allocation of enterprise asset structure. Based on the data of China’s A-share non-financial listed companies from 2011 to 2021, this paper examines the impact of Fintech on enterprise asset structure mismatch, and examines its mechanism and potential heterogeneity. Research has found that fintech can significantly suppress the mismatch of corporate asset structure and optimize the allocation of corporate asset structure. After a series of endogeneity treatments and robustness tests, the conclusion still holds. The moderating effect shows that vertical interlock and financial regulation have a significant positive moderating effect on the mismatch between fintech and asset structure, strengthening the inhibitory effect of fintech on asset structure mismatch; The shareholding of financial institutions has played a significant negative moderating effect, weakening the inhibitory effect of fintech on asset structure mismatch.The intermediary mechanism indicates that corporate financialization and agency costs have played a masking effect, and fintech has further suppressed asset structure mismatches by improving corporate financialization levels and reducing agency costs. Heterogeneity analysis found that in non high tech, heavy asset, eastern regions, high financing constraints, low ESG performance, and low digital economy regions, the inhibitory effect of fintech on asset structure mismatch is more pronounced. Further research has found that fintech suppresses asset structure mismatch and promotes the improvement of total factor productivity and social responsibility of enterprises.