A liquid container includes a liquid chamber and a flexible member. The liquid chamber is configured to contain the liquid. The flexible member is subject to deformation with a decrease in internal pressure of the liquid chamber. The liquid container includes a negative pressure generator configured to maintain negative pressure in the liquid chamber by applying pressure to the flexible member. The liquid container includes a liquid outlet configured to feed the liquid out of the liquid chamber. The liquid container includes an air inlet configured to introduce air into the liquid chamber when the internal pressure of the liquid chamber is lowered to or below a preset level. The liquid container includes a detection-associated member for detection of the remaining volume of the liquid in the liquid chamber. The detection-associated member can be located inside the liquid chamber on a wall of the container body.