Based on the perspective of the spatial distribution of bank branches and outlets on the specific spatial scale around the enterprise, this paper examines the impact mechanism and effect of financial geographic expansion on the enterprises’ cost-plus rate. The study finds that the number of bank branches within 1km，5km and 10km around the enterprise have a significant positive impact on the cost-plus rate, that is, the expansion of financial geography helps to promote the increase of the enterprises’ cost-plus rate; However, the promoting effect is no longer significant at the scale of 15km, indicating that the impact has a spatial decay. The mechanism test finds that the impact between the two mainly through cost reduction effect, innovation-induced effect and market structure effect. The expansion of branches of state-owned commercial banks does not have a significant effect on increasing the cost-plus rate of enterprises; However, in the spatial range closer to the enterprise, non-state-owned commercial banks have a more significant effect. In addition, the expansion of financial geography helps to increase the cost-plus rate of capital-intensive, small, and medium-sized enterprises and private enterprises, but no significant impact on labor-intensive, large and state-owned enterprises. This study provides a new explanation for the mystery of the low cost-plus rate of Chinese enterprises.