Abstract:Er-su Tibetans still retain the original ancient augural custom, which is called "Shi Wo". Er-su Tibetans can have divination at any time. Any incident and anything can be linked to the divination. There are club Gua, rope Gua, Toupa Gua, sheep bladder Gua, pig spleen Gua, ehook head Gua, and so on. In addition, Er-susabas from generation to generation have a book, which is called "Lue Ma Shi Da" in Er-su language. Sahas estimate time and have divination with the help of the book. Divination is the original religion of the area. It is an idea of the worship of nature and mountain god by Er-su Tibetans. After the mid-twentieth century, with the popularization of scientific knowledge, new China has greatly enhanced the quality of the whole people. Er-su Tibetans' concept of materialism is strengthened. Divination act is just as an act of courtesy, in the presence of etiquette. As a relic of the original religion, it has been far away from Er-su Tibetans.