This paper combines the digital transformation speed at the micro-enterprise level with the “cost reduction” and “deleveraging” tasks at the macro-policy level to empirically test the impact of the digital transformation speed on debt financing. The study finds that the speed of digital transformation can effectively inhibit agency risk, information risk and reputation risk, thus reducing corporate debt financing costs and achieving the goal of “cost reduction”. For growing and declining enterprises, enterprises with high level of supply chain integration and intellectual capital, the “cost reduction” effect of the speed of digital transformation is more significant. Based on the research on the optimization of the speed of digital transformation, on the one hand, the acceleration of digital transformation can significantly reduce the debt financing cost, compared with the constant speed and deceleration of digital transformation. The reason for the deceleration of digital transformation to increase the debt financing cost is the marginal diminishing effect of digital transformation rather than the selfinterest behavior of management; on the other hand, the “Broadband China” policy, which reflects the external digital development, and the speed of internal digital transformation have “complementary” effect in reducing the debt financing cost. Based on the research of debt structure optimization from the perspective of “deleveraging”, the speed of digital transformation can optimize the debt maturity structure, debt risk structure and debt capital structure, so as to achieve the goal of “deleveraging”, in which the accelerated digital transformation plays a particularly prominent role.