A liquid-holding container includes a liquid container portion, a hollow vent plug, a first projecting portion, and a second projecting portion. The liquid container portion is flexible and configured to contain a liquid. The hollow vent plug is connected to the liquid container portion. The first projecting portion is connected to the vent plug and extends in a direction that intersects a face of the liquid container portion. The second projecting portion is connected to the vent plug on the opposite side of the vent plug from the first projecting portion. The length of the second projecting portion from a face that includes an axis of the vent plug is shorter than a length of the first projecting portion.