The Flower Watering Festival, called "Sangen" in De'ang language, is the most iconic traditional festival of the De'ang people. It is held on the seventh day after the Qingming Festival in the lunar calendar every year. It is widely spread in Luxi City, Yingjiang County, Ruili City, Longchuan County and Lianghe County of Dehong Dai and Jingpo Prefecture. Among them, the most complete is preserved in Santaishan De'ang Township in Luxi City. From the folk legends of the De'ang people, it can be known that the origin of the Flower Watering Festival is closely related to the introduction of Theravada Buddhism into the De'ang area. The Flower Watering Festival is rich in content. The festival activities are gradually carried out according to eight procedures, including watering Buddha, offering tasting competition, worshiping heaven and earth and chanting sutras to pray for good weather, fetching water for the elderly to wash their hands, singing and passing cigarettes, watering, singing and dancing performances, and sending flower baskets. People wear their best clothes and water the Buddha and Buddha statues to show their remembrance and respect for their ancestors and benefactors. They also wash the dust and celebrate the birthdays of the long-lived elderly over 60 years old to express their gratitude and wishes for them. Next, young men and women splash water on each other, especially on newlyweds, wishing them a harmonious life and happiness. There are specific rules for splashing water: when watering the elderly, you can only use a small bamboo water bottle with fresh flowers and spring water, let the water drip down the bouquet to the palm of the elderly's outstretched hand, not on the body; when young men and women splash water on each other, they must also use a bamboo tube and gently splash from the shoulders, not on the head; when unmarried men and women splash water on newlyweds, they are not allowed to be rude and rude to each other, otherwise, they will be reprimanded by everyone at the least, and deprived of the right to participate in the flower-watering festival at the worst. Sending flower baskets is a special way for De'ang boys to express their love for girls. Before the flower-watering festival, boys are busy weaving beautiful small flower baskets with bamboo strips and giving them to girls who get along well with them on weekdays. The most exquisite flower baskets should be given to the girl they love. Who the girl is interested in depends on who carries the flower basket on the festival. During the festival, the traditional De'ang flower-watering dance is performed, accompanied by three percussion instruments: drums, cymbals, and cymbals. Women carry flower baskets on their backs, while men hold bamboo tubes and pretend to water flowers, indicating that men and women are pouring water on each other to bless each other. The Flower-Watering Festival is a popular festival activity that the De'ang people love and actively participate in. It has a broad mass base and integrates music, dance, and art. It embodies the social customs of respecting the elderly and loving the young, respecting each other, being humble, and living in harmony. It is also a social activity for men and women to express love, and it has played an irreplaceable and positive role in strengthening the aesthetic concepts, artistic tastes, and national character of the De'ang people. With the changes in young people's values and aesthetic tastes, many traditional contents of the Flower-Watering Festival are gradually disappearing.