In recent decades, the tourism industry has become one of the fastest growing industries in the world. The tourism industry's current contribution to global carbon emissions is 4%-6%, and it is estimated that carbon emissions from tourism will increase 1.5 times from its current level by 2035. The emergence of low-carbon tourism represents a transformation in the traditional tourism industry. It is a new trend of sustainable tourism that is changing tourists' pattern of consumption and reducing greenhouse gas emissions. This paper presents the results of a questionnaire survey conducted among tourists visiting Lijiang City, Yunnan Province, China regarding their cognition of and willingness to undertake low-carbon tourism. We show the following: (1) The cognition level of low-carbon tourism was high (68.5%) and showed a significant positive correlation with tourists' education level, hotel rating, and the average number of trips annually. Some tourists stayed in high-rate hotels regardless of energy-extensive consumption to ensure the best quality of their tourism experience, even though they had the highest cognition level. Ninety-one percent of respondents answered that public awareness is the first factor that influences people to choose low-carbon tourism. The concept of low-carbon living, which played a positive role in China, has gradually penetrated into public life. Most respondents answered that a decrease of carbon dioxide emission in tourism could be realized by a change of travel modes (87.5%) and accommodation styles (57.5%). (2) Respondents were generally willing to try low-carbon tourism (79.5%). Willingness to try low-carbon tourism showed a significant negative correlation with hotel rating, the average number of trips annually, and per capita tourist spending. Regular tourists had the highest level of cognition of low-carbon tourism but the least intention to change their way of traveling. Tourists who traveled less often were more willing to try low-carbon tourism. This, however, does little to help effect a change in tourism without the participation of frequent travelers. Tourists' reactions to low-carbon tourism issues can be described as contradictory. Many tourists are aware of the negative impacts caused by traditional tourism and of the need to act. However, most people seem unwilling to sacrifice their personal benefits by voluntarily changing their original consumption patterns. The gap between cognition and action can be attributed to personal benefit. (3) There are certain difficulties and problems involved in the promotion of low-carbon tourism. According to the results of the survey, 46.5% of the respondents believed that low-carbon tourism might just be a catch-phrase or slogan, and 76% of respondents thought that for the time being, tourists in China generally lack the good habits promoted by low-carbon tourism. Encouraging tourists to make voluntary changes in their tourism will be a long-term process in China. Steps to bring about change should focus less on increasing public cognition and more on convincing tourists that minimal changes in their behavior can make a meaningful contribution. (4) Finally, the paper proposes corresponding suggestions to promote low-carbon development from three entities: the government, tourism enterprises and the tourists themselves.