Abstract: Since Yellowstone National Park, the world's first National Park, was established in 1872 in the United States, more than 5000 national parks have been established in 190 countries and regions around the world over the past 150 years. National park has become an important symbolization of national civilization and progress. On October 12, 2021, China officially announced its first batch of five national parks, including the Three-River-Source National Park, Giant Panda National Park, Northeast China Tiger and Leopard National Park, Hainan Tropical Rain Forest National Park and Wuyishan National Park. The establishment of "National Park Day" is a specific action to further promote the development of ecological civilization, the international common practice to strengthen eco-environmental protection, and an essential measure to build a complete anniversary system for ecological protection. It is also an efficient and active step to guide people to love, protect and cherish national parks. The author suggests that 12^th October, the day when President Xi Jinping formally announced the first batch of national parks in China at the Leaders' Summit of the 15^th Conference of the Parties (COP15) of the Convention on Biological Diversity, should be set up as the "National Park Day" in China. National parks in China have just been in its infancy, and there is an urgent need to speed up its top-level design. To celebrate the "National Park Day", we can consider such activities as launching a batch of top-level design, issuing relevant policies and development standards, announcing new batch of national parks, holding "National Park Forum", hosting large-scale science popularization activities, promoting mainstream media for publicity and dissemination, so as to facilitate the healthy and sustainable development of China's national parks.