The water safety is the important part of the national safety system in China, and it concerns the sustainable development of economy and society, the construction of well-off society and the great rejuvenation of China. At present, China has a lot of water safety problems such as uneven spatiotemporal distribution of water resources, low efficiency of water use, acceleration of water pollution, severe damage of water environment and deterioration of water ecology. The key to solve these problems is water-saving, which is also the source for management of water safety. From the relationship between water safety and water-saving, the viewpoint that the water-saving is the basis for the water safety in China is put forward. Based on the researches on the main missions for water saving in three sectors of agriculture, industry and urban living, some advices are proposed so as to practicably implement water-saving and fundamentally guarantee the water safety in China, that is, construction or improvement of compensation mechanism in irrigated areas, reform of agricultural water price, demonstration of water resources for industrial projects, quota management of water use, and performance evaluation system of water-saving to leaders.