As an important tool to achieve sustainable economic and environmental development, green finance can effectively alleviate the financing constraints of small and medium-sized enterprises (SMEs), especially in promoting green transformation plays a key role. SMEs play an important role in economic growth, innovation, and job creation, but due to a lack of collateral, imperfect credit history, and opaque financial information, they face great obstacles in the financing process, especially in the early capital investment required for green transformation. Green finance, through innovative financial instruments such as green credit and green bonds, provides new financing channels for SMEs, helping them reduce financing costs, optimize financing structure, and promote their green transformation and sustainable development. This paper analyzes the current situation and root causes of SMEs’ financing dilemma from the perspective of green finance, and probes into the influence of green finance policies on financing behavior.