Due to hectic city lives and the growing health concerns in light of the global pandemic, mountain tourism has become increasingly popular worldwide, which has increased the related research. Based on traditional bibliometric laws, such as those authored by Price, Bradford, Lotka, and Zipf, this study acquired 1413 mountain tourism journal articles via bibliometric analysis and identified the most influential journal articles, researchers, and countries in mountain tourism research as indexed in the Web of Science (WoS) database during 2010–2020. The keyword analysis revealed mountain tourism’s emerging research topics, including climate change, sustainable development, sustainability, sustainable tourism, protected areas, rural tourism, and conservation. The most influential journal was Sustainability in the mountain tourism. The research results showed that China, the U.S., and Romania produced the most significant mountain tourism articles indexed in the WoS. Most developed countries in Europe had the highest average and average normalized citations, which indicated that they may have more influence in this field as compared to other countries. Some developing countries, such as India, Nepal, and China, had higher citations, average citations, and/or average normalized citations than other countries. The main research trend was the sustainable development aspect of mountain-based tourism during the COVID-19 pandemic. We identified the research gap in WoS; although there is some research shedding light on tourism via bibliometrics, mountain tourism bibliometric analysis and science mapping via VOSViewer is scarce. The paper summarizes the critical aspects of the current discussion of sustainable mountain tourism, such as transport and coopetition (i.e., combing with cooperation and competition) in mountain tourism areas. The results indicated that government agencies and destination managers need to strike a balance between sustainable mountain tourism development and environment and natural landscape conservation after COVID-19.