A liquid cartridge capable of being attached to or detached from a predetermined apparatus includes: a container which stores a liquid; a supply port which supplies the predetermined apparatus with the liquid stored in the container; an air communication hole which allows the container to communicate with the atmosphere; and a valve mechanism capable of switching between opening and blocking of the air communication hole. The valve mechanism includes a valve element which can be brought into intimate contact with the air communication hole to block the air communication hole, and a lever which moves, while rotating, between a first position in which the valve element is brought into intimate contact with the air communication hole and a second position in which the valve element is separated from the air communication hole in response to attaching/detaching of the liquid cartridge to/from the predetermined apparatus.