4th century to14th century. Among the Mogao Grottoes in Dunhuang, Gansu, China, there are many images of "flying" in the grottoes in Dunhuang area, which lasted more than 1000 years from the 4th century (Sixteen Kingdoms) to the 4th century14th century (Yuan Dynasty). This is a treasure of national art, and it is a dazzling flower in Buddhist art. The early "flying sky" in Dunhuang was painted on the corner of grottoes, the decoration of algae wells on grottoes, the upper edge of niches and the heads of main characters in bunsen burner's story paintings. During the Northern Wei Dynasty, the scope of "Tian Fei" painting has been extended to illustrations and Buddhist niches. Tian Fei in Sui Dynasty is in a period of integration, exploration and innovation, which is mainly manifested in its different shapes, slender figure, moderate proportion, soft waist and graceful appearance. The four murals in the Tang Dynasty caves are all large-scale paintings, and "flying" is not only painted on seaweed, shrines and four curtains. After the Five Dynasties and the Song Dynasty, "Tian Fei" did not innovate in modeling, and gradually formulated. The "flying" in Dunhuang murals appeared at the same time as the cave opening, which lasted for more than 1000 years from the Sixteen Kingdoms to the end of the Yuan Dynasty.