To efficiently and correctly conduct survey of a contamination state in the ground.

There is provided an underground sampling device 1 mainly formed of a hollow cylindrical boring pipe 2 and a sample taking attachment 3 arranged at the tip of the hollow cylindrical boring pipe. The hollow cylindrical boring pipe 2 has a sample storage bag inserted in a hollow interior thereof. The sample storage bag may be any one insofar as it satisfies the following conditions. That is, it has a sufficient length with respect to a sampling depth or a depth at which the contamination survey is conducted, it is easily insertable into the hollow cylindrical boring pipe 2, and it is formed of a water-sealing material having required tensile strength in order to withstand a tensile force caused by earth into which the hollow cylindrical boring pipe 2 is squeezed according to rotational press-fitting of the pipe 2 into the ground. The sampling attachment 3 consists of a sample introducing hollow cone 15 and a cone receiver 14, and functions to pinch a sample introducing edge of the sample storage bag 11 between the cone 15 and the receiver 14.