Abstract: There is still a lack of causal inference based on a large sample of data as to whether China’s Global Geoparks can promote tourism development. The difference-in-difference (DID) model is used to identify the impact of China’s Global Geoparks on tourism development. The model is based on panel data of 185 cities from 2003 to 2020. Full-sample estimations show that China’s Global Geoparks do not have a significant impact on tourism development. Further analyses reveal that the effects of China’s Global Geoparks on tourism development are heterogeneous in four dimensions: economic level, tourism resources, transportation infrastructure and administrative level. Specifically, these effects are manifested in promoting the tourism development of disadvantaged cities while inhibiting the tourism development of advantaged cities.