A gas chromatography device includes a sample injection part, a detector, a separation column, and a transfer line connecting between the sample injection part and the separation column and between the sample injection part and the detector. Furthermore, a column temperature adjustment part for adjusting the temperature of the separation column, and a line temperature adjustment part for adjusting the temperature of the transfer line are provided. The line temperature adjustment part is structured to include a heat block which includes a heating element and which is in contact with the transfer line from one side, and a holding member which presses the transfer line toward the heat block side by being in contact from the other side, and to sandwich the transfer line by the heat block and the holding member.