To provide an automatic penetration test machine that is equipped with a cooling mechanism for a lifting/lowering motor.

An automatic penetration test machine 1 is constructed so that a rotational motor 6 is driven in reverse at a high speed according to a detection value of a temperature sensor 40 of the rotational motor 6 and a one-way clutch 35 intervened in a drive transmission system slips. Thereby, a drive shaft 6a of the rotational motor 6 rotates at a high speed with no load applied thereon. As a cooling fan 6b rotates at a high speed along with the rotation of the drive shaft 6a, the rotational motor 6 can be sufficiently cooled.