Abstract: Financial technology (FinTech), represented by blockchain, helps mitigate the problem of information asymmetry in traditional supply chain finance, thereby alleviating the financing difficulties faced by small and medium-sized enterprises (SMEs). However, enterprises often exhibit free-riding behaviour in FinTech investment, and how government subsidies can effectively guide enterprises to engage in such investment remains insufficiently explored. Therefore, an evolutionary game model between banks and financial companies under the condition of government subsidies is constructed, with the purpose to systematically analyses additional ecological benefits from unit output effect, investment cost, and technological investment, as well as the impact of free-riding behaviour on enterprises′ FinTech investment strategies. The results show that when the unit output effect of FinTech investment is at a moderate level, the evolutionary equilibrium converges to two different stable states (i.e., only the bank or only the financial company participates in investment). The additional ecological benefits brought by technological investment and the gains from free-riding behaviour determine the specific investment strategies adopted by enterprises. Moreover, both the magnitude and the asymmetry of government subsidies significantly influence enterprises′ willingness to invest in FinTech: 1) only when subsidies for both banks and financial companies reach relatively high levels will both parties jointly invest in FinTech; 2)when subsidies for both are low, the equilibrium still converges to a single-party investment outcome; 3)when subsidies are asymmetric, the party receiving less subsidy tends to opt out of investment, leading to a subsidy bias effect that discourages the weaker side from investing. Finally, profits from free-riding behaviour substantially weaken enterprises′ investment incentives. Effective stimulation of proactive investment can only be achieved when government subsidies cover the gap between investment costs and free-riding gains, or when technological protection mechanisms are employed to reduce free-riding benefits.