The Deang people's sour tea making technique is a traditional technique of Mangshi City, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province, and one of the national intangible cultural heritages. The Deang people are a minority ethnic group living across the China-Myanmar border in southwestern Yunnan, China. They have a long history of tea planting, tea drinking and tea-using customs and are known as "ancient tea farmers". The Deang people's "sour tea", also known as wet tea, is made by picking fresh tea leaves from the local Santaishan large-leaf variety and sealing them in bamboo tubes for fermentation. It is made purely by hand using ancient methods. The tea tastes sour and astringent, and tastes sweet after bitterness. The tea color is golden and translucent, with a unique sour cheese aroma, which can quench thirst, relieve summer heat, and help digestion. There are two techniques for making sour tea for the Deang people: one is the earth pit method, which is the method of making sour tea before humans invented pottery. The other is the pottery method, which is to directly use pottery to pickle sour tea after pottery has been widely mastered and used by people. The De'ang sour tea making technique belongs to the ancient method of tea making, which is completely handmade. The tea has a unique taste, slightly sour, bitter and sweet, and the tea color is golden and translucent, with a unique sour cheese aroma. The De'ang sour tea has rich connotations and diverse forms of tea customs. It has special uses in love life, marriage customs, interactions with relatives and friends, religious sacrificial activities, etc. It has strong ethnic characteristics and fully demonstrates the De'ang culture and national values. On May 24, 2021, the De'ang sour tea making technique applied by Mangshi, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province, was approved by the State Council to be included in the fifth batch of national intangible cultural heritage representative projects, with the heritage number: -268.