This study compared tourists’ demographic variables between survey data and Twitter data in Yellowstone National Park and explored tourists’ experience through Twitter data. First, there were significant differences in age groups of tourists between social media data and survey data. Compared to survey data, tourists who identified by Twitter data concentrated on middle age groups. Secondly, the spatial distribution of geotagged tweets reflected the road network and main attractions in Yellowstone National Park. The peak visitation season is from June to September in survey data, while, in social media data, the peak visitation season is slightly shorter. Finally, the sentiment analysis was conducted and only 6.7% of tweets were negative, indicating that most tourists in Yellowstone National Park had good experience. Therefore, analyzing Twitter data will be helpful for understanding tourists’ demographics, attitudes and experience in the national parks and improving customer service in the further.