PROBLEM TO BE SOLVED: To provide an infusion solution bag suitable for retaining at a high level, gas barrier property which a film material has, even if receiving physical stress.SOLUTION: An infusion solution bag including a film material as a partition wall partitioning an inner part and an outer part for storing an infusion solution is such that the film material includes a multilayer structure having at least one layer each of a base material (X), a layer (Y) and a layer (Z). The layer (Y) contains aluminum atoms, and the layer (Z) contains a polymer (E) containing a monomeric unit having phosphorus atoms. In the multilayer structure, at least one pair of the layer (Y) and the layer (Z) is laminated adjacently.
