Building reservoir is one of the important methods that many countries control the floods and resolve other water problems. Although it can produce much economic interests, it also causes considerable environmental damage, especially on such highly sandy river as the Yellow river. It is because the constantly construction of reservoirs in decades that changed the water and sands conditions of the Yellow river violently. Firstly, the fundamental influence mechanism of water and sands problems of the Yellow river from natural and artificial factors is presented. From the analysis on sediment and water volume of temporal and spatial data of runoff elaborately, the negative effect of the reservoirs (especially Longyangxia reservoir, Liujiaxia reservoir and Sanmenxia reservoir) on water and sands problem of the Yellow river can be recognized, which is that frequency of middle and high water volume was reduced, the sediment accumulation was increased, the current was artificially controlled highly, and the broken current was more severe. Finally the relevant strategy is suggested from the view of sustainable development.