Abstract: The Huaihe River originates in the Tongbai Mountains and used to flow past Huaiyin and empty into the sea in the east, thus forming the Huaihe River delta. In A.D. 1128-1885, the Yellow River changed its course and its mud and silt blocked the course of the ancient Huaihe River to the sea, thus forcing the Huaihe River to turn to the south and flowed into the Yangtze River. Then the Huaihe River delta has not been mentioned by the people. According to the regional geological structure, the paper addresses the development of the Huaihe River drainage system and formation of the Huaihe River delta, as well as the Quaternary sea transgression and regression and evolution of fresh and saline water. This study provides a scientific basis for the understanding of the development and evolution of the tail of the Huaihe River.