Under the background of advocating green and low-carbon economic development, Chinese heavy polluting enterprises are in urgent need of technological innovation to realize a green transition to low energy consumption and low emissions. This paper focuses on 97 Chinese heavy polluting listed enterprises as the research subject, examining the influence of financial support and technological innovation on the environmental performance of these enterprises. It conducts empirical analysis from two perspectives: policy-based financial support and market-oriented financial support, exploring both the direct impact of financial support on environmental performance and its indirect impact through technological innovation. The findings demonstrate the significant direct and indirect impacts of policy-based financial support on the environmental performance of Chinese heavy polluting enterprises. Specifically, in terms of indirect effects, policy-based financial support can effectively enhance the environmental performance of these enterprises through technological innovation. Moreover, the total effect, direct effect and indirect effect of market financial support on the environmental performance of Chinese heavy polluting enterprises are also significant, this confirms that market financial support may facilitate technological innovation to improve the environmental performance of Chinese heavy polluting enterprises.. After conducting an analysis, it is determined that policy-based and market-based financial support for Chinese heavy polluting enterprises can be effectively increased. This will improve the enterprises' capacity for technological innovation and will also help to improve their environmental performance in China.