Mooncake festival is also called Mid-autumn festival. Celebration of Mid-autumn festival has a long history. In ancient times, the emperors had the tradition of worshiping the Sun in spring, and the Moon in autumn. The word “Mid-Autumn” first appeared in the famous ancient book “Zhou Li” (The Zhou Rituals, a book telling the rituals in the Zhou Dynasty). However, it was not until the early Tang Dynasty that the day was officially celebrated as a traditional festival. It became a established festival during the Song Dynasty, and has become as popular as the Spring Festival since the Ming and Qing Dynasties. Celebrations has continued ever since and more customs for marking this occasion have been formed.