Dai is one of the 56 nationalities in China, with a population of 1,075,128, mainly residing in Yunnan Province: Xishuangbanna Autonomous Prefecture of Dai Minority, Dehong Autonomous Prefecture of Dai and Jingpo Minority, Dima, Menglian, Jinggu, Xinping, Jinping, Yuanjiang, and Shuangjiang.

The Dai is a nationality of great antiquity. Their ancestors in the time of the Han and the Jin Dynasties were called "Dianyue", "Dan", "Shan", "Liao" and "Jiuliao", while their residing areas were called the Elephant Riding Country; in the time of the Tang Dynasty and the Song Dynasty, they were called "Mangman", "Jinchi (Gold Teeth)", "Yinchi (Silver Teeth)", "Baiyi (White Robe)", etc.; in the Yuan Dynasty and the Ming Dynasty, they were called "Baiyi (White Robe)", "Baiyi (Hundred Minority)"; "Baiyi" (Bai Robe) or "Baiyi" (Bai Minority) since the Qing Dynasty. (Each of the above four "Baiyi" has different written and pinyin forms in Chinese)

The name Dai is what they call themselves. According to different distribution districts, there are also names of "Daili", "Daiya", "Daina", "Daibeng", "Daiduan". Since the founding of the People's Republic of China, they are finally unified under one name Dai, according to their own wish. Besides, The Dai people in different districts, with their respective customs and raiments, are distinguished as "Han Dai (Land Dai)", "Shui Dai (Water Dai)" and "Huayao Dai (Festoon Waist Dai)".

The Dai people have their own language in both a written form and a spoken form. The Dai language belongs to Chinese-Tibetan Family Zhuang and Dai subgroup of Zhuang and Dong branch, Sino-Tibetan family, originated from writing letters of Sanskrit. The language used to have four types: Daili, Daina, Daibeng and Jinping, and now only two systems of writing letters - Xishuangbanna and Dehong - are vulgate.