A calibration device for calibrating a gas component analyzing apparatus for analyzing by detecting a component of a sample gas by a detector, which is separated as a single component through a separation unit, wherein the separation unit is connected to a supply tube providing a gas thereto, wherein the calibration device comprises: one side connection part (V100, L100) selectively connectable to one point of the supply tube; one other side connection part (V200, L300) selectively connectable to one other point of the supply tube; characterized in that the calibration device further comprises: a calibration line part comprising a plurality of connection tubes (110, 120, 130, 140, 150) parallel-connecting the one side connection part (V100, L100) to the other side connection part (V200, L300) in different paths from each other;wherein the plurality of connection tubes (110, 120, 130, 140, 150) have different volumes from each other, and a control unit configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) with a calibration gas source to fill the connection tubes (110, 120, 130, 140, 150) with a calibration gas, wherein the control unit is further configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) filled with the calibration gas with the supply tube to provide a plurality of calibration gases having different volumes. one side connection part (V100, L100) selectively connectable to one point of the supply tube; one other side connection part (V200, L300) selectively connectable to one other point of the supply tube; characterized in that the calibration device further comprises: a calibration line part comprising a plurality of connection tubes (110, 120, 130, 140, 150) parallel-connecting the one side connection part (V100, L100) to the other side connection part (V200, L300) in different paths from each other;wherein the plurality of connection tubes (110, 120, 130, 140, 150) have different volumes from each other, and a control unit configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) with a calibration gas source to fill the connection tubes (110, 120, 130, 140, 150) with a calibration gas, wherein the control unit is further configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) filled with the calibration gas with the supply tube to provide a plurality of calibration gases having different volumes. a calibration line part comprising a plurality of connection tubes (110, 120, 130, 140, 150) parallel-connecting the one side connection part (V100, L100) to the other side connection part (V200, L300) in different paths from each other;wherein the plurality of connection tubes (110, 120, 130, 140, 150) have different volumes from each other, and a control unit configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) with a calibration gas source to fill the connection tubes (110, 120, 130, 140, 150) with a calibration gas, wherein the control unit is further configured to sequentially connect the connection tubes (110, 120, 130, 140, 150) filled with the calibration gas with the supply tube to provide a plurality of calibration gases having different volumes.