As an important transportation infrastructure, high-speed railroad has a significant impact on the development of tourism in ethnic areas. Tourism resources in ethnic areas are rich but underdeveloped, and the opening of high-speed railways provides guarantee for tourism convenience and promotes the expansion of the source market. Based on Data Envelopment Analysis (DEA) and Double Difference Method (DID), this study utilizes the panel data of Region B from 2012-2018 to explore the enhancement effect of the opening of high-speed railroads on the economic benefits of the tourism industry in ethnic regions. The study adopts the DEA-BCC model to assess the comprehensive efficiency of the tourism industry, utilizes the DEA-Malmquist index to measure the change in total factor productivity, and employs the PSM-DID method to assess the impact of the opening of high-speed railways on the economic development of tourism. The results of the study show that: the overall comprehensive efficiency of tourism in Region B shows an upward trend, with an average value of 0.45 during 2012-2018, reaching a maximum value of 0.80 in 2018; the Malmquist index analysis shows that the index of total factor productivity change has increased by 0.1% annually, of which the index of technical efficiency change has increased by 0.6% annually, and the index of technological progress has declined by 0.5% annually; the double difference analysis shows that the opening of high-speed rail significantly improves the level of tourism economic development of cities in ethnic areas along the route, and the coefficient of the core explanatory variable is 0.122, and it is significant at the 5% level. The mechanism analysis shows that the high-speed rail promotes the rise of green economic efficiency of urban tourism through the channels of increasing the scale output of tourism, promoting the upgrading of industrial structure and upgrading the level of urban greening. The study confirms that the opening of high-speed railways has an obvious promotion effect on the tourism economic development of ethnic areas, and provides a scientific basis for the tourism policy formulation and transportation infrastructure construction in ethnic areas.
