To provide a method for collecting a volatile component in soil with a high sampling accuracy, and a collecting apparatus therefor by which the volatile component in a soil gas can be collected in a short time, and which can be applied to both a high-sensitivity method and an intermediate-sensitivity method while providing consistency between the methods without fears of sucking the outside air on the ground contaminated with the volatile component.

A suction pipe 4 and a discharge pipe 5 are inserted into a collection hole A through a lid body 3 which seals the collection hole A formed in the soil at a ground surface. A collection pipe 1 for the volatile component in which adsorbents 2a and 2b are filled is connected to an open end at the ground side of the suction pipe 4. The soil gas in the collection hole A is sucked for a predetermined time by a quantitative pump 6, so that the volatile component is adsorbed to the collection pipe 1. At the same time, the soil gas discharged from the quantitative pump 6 is guided to an absorber 7, and turned to a clean air to return from the discharge pipe 5 into the collection hole A.