Low-carbon economy has become the current global economic development trend, and corporate carbon disclosure has attracted more and more attention from scholars and investors. This study creatively explores the mechanism of corporate carbon disclosure on total factor productivity with financing structure as a mediating variable. The content analysis method is employed to assess carbon disclosure that is suitable for Chinese enterprises. Through the mediating effect model and Sobel test, the internal mechanism of carbon disclosure affecting total factor productivity is analyzed, with Chinese heavy polluting enterprises from 2015 to 2018 as research samples. The results show that, firstly, carbon disclosure has a positive effect on the improvement of total factor productivity. The effect of monetary carbon disclosure on the improvement of total factor productivity is higher than that of non-monetary carbon disclosure. Secondly, the financing structure has a mediating effect between carbon disclosure and total factor profductivity, and the mediating effect of internal financing capabilities is better than those of external financing costs. Finally, external financing costs and internal financing capabilities have mediating effects in both heterogeneous carbon disclosure and total factor productivity. The mediating effect of internal financing capabilities is significantly higher than the mediating effect of external financing costs. The effect of monetary carbon disclosure on total factor productivity indirectly through internal financing capabilities is higher than that of non-monetary carbon disclosure.