To provide a sampler for investigating soil contamination having no possibility of outflow of sediment even when water is supplied to the distal end.

This sampler comprises an outer tube, a first head threaded to the upper end of the outer tube, a bit threaded to the lower end of the outer tube, a first inner tube disposed in the outer tube so that a first space can be formed between the first inner tube and the inner surface of the outer tube, a second inner tube disposed in the first inner tube so that a second space can be formed between the second inner tube and the inner surface of the first inner tube and in which a specimen to be sampled is stored, a seal material disposed between the lower end of the second inner tube and the bit and cutting off a communication between the inner part of the second inner tube and the second space, a second head threaded to the upper end of the second inner tube and rotatably fitted to the lower end of the first head, a hollow boring rod threaded to the first head, and one or a plurality of hoses connected to the upper end of the first head.