The present invention is a gas absorption device arranged in a liquid container storing a liquid fed to a liquid consumption apparatus. The device includes a decompressed container having an opening and a flexible film sealing the opening in the state that the decompressed container is internally decompressed. At least a part of a portion having an inner surface which receives the decompressed pressure in the decompressed container and an outer surface which is in contact with the liquid in the liquid container is formed by a gas permeable material through which gas dissolved in the liquid in the liquid container can permeate. According to the present invention, gas dissolved in the liquid stored in the liquid container can be absorbed using a decompressed space and the existence of a decompressed status necessary to absorb gas can be easily examined.