Transportation infrastructure,as the backbone of the transportation sector,plays a crucial role in the realization of the government's"dual carbon goals"in the transportation domain.This study explores the carbon emissions of 34 Shanghai and Shenzhen A-share listed transportation infrastructure companies in 20 provinces(autonomous regions,municipalities)in China from 2012 to 2021,and analyzes the mechanism of government subsidies on the carbon emission intensity of transportation infra-structure enterprises using a dual mediation model.The research findings indicate that:(1)Government subsidies can significant-ly mitigate the carbon emission intensity of transportation infrastructure enterprises;(2)Green transition and Environmental regu-lation serve as mediators in suppressing carbon emissions of transportation infrastructure enterprises.This study provides impor-tant insights for the government in formulating environmental policies and subsidy schemes,thereby facilitating the sustainable development of the transportation infrastructure industry.