Through analysing related data it is clarified that the rising range of flood water level is limited only in the Jingjiang reach and Chenglingji Luoshan reach. In studying the mechanism of flood water level rise, the author considered that the main reason is the results of the influence of human activities. So ,to standardize the action of people in regulation and development of river and to control the influence of human activities are the important measures for controlling flood water level rise. 