The present invention relates to a device for absorbing carbon dioxide, which is equipped along an automobile exhaust pipe and a factory chimney. The present invention also relates to a method for absorbing carbon dioxide. According to the present invention, there is provided a device for absorbing carbon dioxide, comprising a housing 4 of a material having air permeability; a cement composition for absorbing carbon dioxide, enclosed inside the housing 4; and a pipe 5 across the housing, the pipe having an inlet 2 and an outlet 3. According to the present invention, when a gas is introduced from the inlet 2, carbon dioxide in the gas is absorbed by the carbon dioxide absorbing materials such as a cement composition enclosed in the housing 4. The gas is discharged from the outlet 3.