A liquid storage bag for solving the problem that liquid in a conventional liquid storage bag easily leaks or flows backward from an input port. The system includes: a bag body having an accommodating space and an injection port connecting the accommodating space; and an input tube having a first opening, a second opening, and the first opening and the second opening a liquid flow channel, the second opening is connected to the injection port of the bag body, a partitioning member is disposed in the liquid flow channel, the partitioning member has two surfaces and at least one perforation extending through the two surfaces, and a checker is combined The partition member faces the second opening, and the check member is pushed by the liquid to be elastically deformed to shield or not shield the perforation of the partition.一種儲液袋,用以解決習知儲液袋中的液體容易從輸入口漏出或倒流的問題。係包含:一袋體,具有一容置空間及連通該容置空間的一注入口;及一輸入管,具有一第一開口、一第二開口,及連通該第一開口及該第二開口的一液流通道,該第二開口係連接該袋體之注入口,一分隔件設於該液流通道,該分隔件具有二表面及貫穿該二表面的至少一穿孔,一止逆件結合於該分隔件並朝向該第二開口,該止逆件受液體流動而被推動產生彈性變形,以遮蔽或不遮蔽該分隔件之穿孔。