PURPOSE: To carry out the storing work without using another auxiliary device such as a winch, in a storing method in which a thrust cylinder is stored in a leader in order to reduce the transporting height in a transporting condition, in an earth drill.

CONSTITUTION: This storing device is composed of a thrust cylinder A pivoted to the storing part on top of a leader, and held by a parallel link mechanism which consists of a link 4 regulated by pins 6, and a link 5 provided at the upper side than the link 4; and a link 7 for storing and assembling pivoted at the lower side of one side link 4 to compose the parallel link mechanism. The rod A of the thruster cylinder A is extended in the storing time, and after it is connected to the link 7 for storing and assembling, the rod A is contracted, so as to store the thruster cylinder A in the leader 1 by laying down the parallel link mechanism.