In the era of information technology, Big Data analytics enable us to get the updated information and have an in-time overview of certain situations. With the help of Baidu Index, a kind of Big Data, we can figure out the top 5 popular tourism sites in China, and how bad they have been influenced in pandemic, as well as what degree they have rebounded in the post-pandemic era. By analyzing the data of Baidu Index, comparing this data in the beginning of pandemic and in post-pandemic era with that in the normal situation, we find that, while there is no record for search query keyword: COVID-19 or Coronavirus updated news, tourism in china's top three hot cities, as well as in Wuhan had high demand, while The search index record of COVID-19 remained a high value, The search index record of Travel Guides reached its minimum value correspondingly. From the breakdown of searcher image, it shows Xian is the most popular tourism destination in East, North and Northwest China. At last, we proposed suggestions to promote the further development of tourism industry in China.