Foreign direct investment (FDI) serves as a pivotal external driver for the low-carbon transition in developing host countries. However, its environmental impact remains theoretically contested between the “pollution halo” and “pollution haven” hypotheses. While prior studies have predominantly examined its effects in manufacturing and energy sectors, limited attention has been given to its impacts on service industry. This study fills the existing research gap by applying a panel threshold model with two-way fixed effects, using provincial panel data from 30 Chinese provinces spanning 2007-2022. It investigates the nonlinear relationship between FDI and the low-carbon development in tourism (LCDT), with a particular focus on the moderating roles of green taxation (GTAX) and green technological innovation (GTI). The empirical findings reveal that: (1) FDI, GTAX, and GTI each significantly promote the LCDT; (2) GTI positively moderates the relationship between FDI and LCDT, whereas GTAX exhibits a negative moderating effect; and (3) these moderating effects demonstrate regional heterogeneities. Theoretically, this research extends the environmental impact literature of FDI to the service sector and uncovers the multifaceted mechanisms driving LCDT. Practically, it offers scientific basis for guiding the refined design and adjustment of GTAX policies, optimizing regional low-carbon governance plans, thereby supporting China’s tourism sector in leveraging opportunities from the restructuring of global green supply chains.