To perform the analysis of a low boiling point substance to a high boiling point substance at one time by an easy and highly sensitive thermal desorption method by comprising three or more filler layers, and filling glass beads in the first layer and a graphite carbon black adsorbent in the second and following layers.

The average grain size of the glass beads which effectively adsorb a high boiling point substance is preferably set to 60-80 meshes since the desorption of the high boiling point substance is difficult in the introduction to a gas chromatograph when it is too small, and the efficiency of adsorption of the high boiling point substance from the atmosphere is deteriorated when it is too large. The specific surface area of the graphite carbon black adsorbent is preferably set to 5-200 m2/g since the thermal desorption rate after adsorption of the high boiling point substance is deteriorated to significantly reduce the recovering ratio when it is too large. The filling quantity of each adsorbent is properly set so that the thickness of each filling layer is within the range of the first layer : the second layer : the third layer = (1:2:1)-(1:3:2)when three layers are used.