<p>Digital Financial Services (DFS) are reshaping the development trend and pattern of financial and other fields, and have the potential to be the heart of financial transformation in future. However, the diffusion of DFS is still very limited in the real complex context. To explore the diffusion mechanism of DFS, this study constructs an evolutionary game model in complex network in which financial institutions, Small and Medium-sized Enterprises (SMEs) and the government play the role together. Then we analyze the evolutionary strategic stability (ESS) of each participant and explore the impacting factors on ESS. Thereafter, based on the multi-layer complex network, we conduct numerical simulation analysis to examine the sensitivity of factors affecting the strategic decisions of game stakeholders. The findings indicate that (1) There are three stable equilibrium points in the game system, corresponding to the three stages of DFS diffusion. (2) DFS exist a significant cost threshold. (3) The social benefits have more profound effect on the diffusion rate of DFS than additional benefits. (4) For the incentive effect of the government, the subsidy intensity for financial institutions providing DFS exhibits a greater sensitivity compared to the lost benefits. In addition, the subsidy intensity plays more significant role than tax relief in promoting the diffusion of DFS. Our exploration provide insight into the diffusion of DFS from the perspective of demand and supply sides, and also provide effective reference for the formulation of relevant policies.</p>