A liquid storage unit includes a liquid container, a spout, a plate-shaped member, and a bag. The liquid container is provided with a storage portion configured to store a liquid inside of a flexible sheet. The spout is provided on the liquid container, and is configured to supply the liquid stored in the storage portion to an inkjet printer in a state in which the spout is connected to the inkjet printer. The plate-shaped member is configured to sandwich at least a portion of an end portion of the liquid container from both sides in an orthogonal direction that is orthogonal to a surface of the sheet. The bag is configured to enclose the liquid container and the plate-shaped member. An inside surface of the bag contacts the plate-shaped member when the inside of the bag is in a depressurized state.