Low-carbon transition in carbon-intensive industries is crucial for achieving climate targets. However, it's challenging for enterprises and projects in these industries to access the necessary funding for their transition within the existing financial system. In this context, transition finance supports the low-carbon transition of carbon-intensive industries, injecting momentum into achieving carbon neutrality goals. However, the precise impact of transition finance on the macroeconomy remains uncertain, and the effective strategies for its implementation to effectively advance national climate objectives are still unclear. This study integrates the stock-flow consistent method into a computable general equilibrium model to evaluate the macroeconomic impact of transition finance supporting China's climate goals. Results indicate that promoting investment in energy systems capital within carbon-intensive industries through transition finance can reduce the economic cost of achieving carbon reduction targets in China, with a reduction ranging from 0.02 % to 0.26 %. Additionally, transition finance optimizes the energy structure in the short term, mitigates the exit of high-carbon industries, and lessens the impact of climate targets on these enterprises. However, implementing transitional financing requires enhanced information disclosure and strict regulation of fund flows to mitigate potential credit risks. The research findings provide valuable insights into China's transition finance policy formulation and serve as a reference for other regions seeking financial support to achieve climate targets.