A liquid container, operable to supply a liquid to a liquid ejecting apparatus, the liquid container comprising: a liquid containing portion capable of containing the liquid; and a liquid supply portion one end of which is connected to the liquid containing portion and the other end of which includes an opening which opens outwardly, the liquid supply portion allowing for the liquid to flow from the liquid containing portion to the liquid ejecting apparatus, the liquid supply portion including a liquid detecting portion which is operable to detect an amount of the liquid in the liquid container and which includes: a liquid detection chamber for containing the liquid supplied from the liquid containing portion; and a sensor that is disposed in the liquid detection chamber and for outputting a detection signal which is used to detect the amount of the liquid in the liquid container, wherein the sensor is configured to change the output state of a detection signal depending on negative pressure generated in the liquid detection chamber, wherein the supply portion further includes: a first flowpath in which the liquid detection chamber is not disposed and which allows the liquid when contained in the liquid containing portion to flow to the liquid ejecting apparatus without passing through the liquid detection chamber; and a second flowpath in which the liquid detection chamber is disposed and which allows the liquid contained in the liquid containing portion to pass through the liquid detection chamber and then flow to the liquid ejecting apparatus, and the first flowpath and the second flowpath are formed in parallel with each other. a liquid containing portion capable of containing the liquid; and a liquid supply portion one end of which is connected to the liquid containing portion and the other end of which includes an opening which opens outwardly, the liquid supply portion allowing for the liquid to flow from the liquid containing portion to the liquid ejecting apparatus, the liquid supply portion including a liquid detecting portion which is operable to detect an amount of the liquid in the liquid container and which includes: a liquid detection chamber for containing the liquid supplied from the liquid containing portion; and a sensor that is disposed in the liquid detection chamber and for outputting a detection signal which is used to detect the amount of the liquid in the liquid container, wherein the sensor is configured to change the output state of a detection signal depending on negative pressure generated in the liquid detection chamber, a liquid detection chamber for containing the liquid supplied from the liquid containing portion; and a sensor that is disposed in the liquid detection chamber and for outputting a detection signal which is used to detect the amount of the liquid in the liquid container, wherein the sensor is configured to change the output state of a detection signal depending on negative pressure generated in the liquid detection chamber, wherein the supply portion further includes: a first flowpath in which the liquid detection chamber is not disposed and which allows the liquid when contained in the liquid containing portion to flow to the liquid ejecting apparatus without passing through the liquid detection chamber; and a second flowpath in which the liquid detection chamber is disposed and which allows the liquid contained in the liquid containing portion to pass through the liquid detection chamber and then flow to the liquid ejecting apparatus, and the first flowpath and the second flowpath are formed in parallel with each other. a first flowpath in which the liquid detection chamber is not disposed and which allows the liquid when contained in the liquid containing portion to flow to the liquid ejecting apparatus without passing through the liquid detection chamber; and a second flowpath in which the liquid detection chamber is disposed and which allows the liquid contained in the liquid containing portion to pass through the liquid detection chamber and then flow to the liquid ejecting apparatus, and the first flowpath and the second flowpath are formed in parallel with each other.