Stories about Tao Wu (the original name of Baosheng Dadi) were documented by Yu Sun, Zhi Yang, Xia Zhuang, Dexiu Zhen and Kezhuan Liu in the Song Dynasty, which is around 50-200 years after the time of Tao Wu. These five people all grew up in Fujian, China, which is geographically close to where Tao Wu lived. Their written works serve as first-hand historical materials to study belief in Baosheng Dadi. From the Song Dynasty to the Qing Dynasty, there is also some documentation about Tao Wu, but the stories vary in details or even in the facts reported. Though Tao Wu was known as God of Medicine, there is no record relating to his life or anecdotes about him. It was not until 50 years after his death that people started writing about him and regarding him as a god. Thus, instead of investigating historical facts, study of how his believers perceive him may be more helpful in understanding and tracing the development of the belief in Baosheng Dadi. The present study discusses the origin and development of belief in Baosheng Dadi from his life, miracles associated with him, religious documentation, titles given to him, and his characteristics as a god.