<p>Against the backdrop of China’s ongoing efforts to achieve carbon peaking by 2030 and carbon neutrality by 2060, reducing the carbon intensity of industrial enterprises is crucial for achieving national emission reduction targets and promoting sustainable corporate development. This paper uses Chinese industrial enterprises as a sample to systematically study the impact and mechanism of political connections on corporate carbon intensity. Based on panel data empirical analysis, this paper examines the direct effect of political connections, the mediating role of technological innovation efficiency, and the reverse moderating effect of rent-seeking behavior, and further investigates industry competition and regional heterogeneity. Empirical results show that political connections significantly reduce the carbon intensity of industrial enterprises; technological innovation efficiency plays a partial mediating role between political connections and carbon intensity; rent-seeking behavior weakens the emission reduction effect of political connections; and, Moreover, political connections exert a more pronounced incentive effect on emissions reduction among enterprises in low-competition industries and in China’s more economically developed eastern regions. This study indicates that political connections not only affect corporate environmental performance but also play an indirect role by improving technological innovation efficiency, with the effect moderated by corporate behavior and market competition conditions. The findings provide important insights for enterprises to rationally utilize political connections to promote low-carbon transformation, improve innovation incentive mechanisms, and formulate policies.</p>