To provide a moving device for a member press-in work device of not becoming high weight and of not overhanging to the side.

In a member press-in work device having a member press-in mechanism on a base frame and having a vertically freely extending/contracting outrigger on the base frame 1, the device has a longitudinal travel driving hydraulic cylinder 13 for slidingly receiving/supporting the base frame 1 in the longitudinal direction by a pair of longitudinal directional traveling plates 10 existing in a landing possible position under the base frame 1 in the mutually opposing both end parts and sliding the base frame 1 and the traveling plates 10 in the mutually longitudinal opposite direction, and the outrigger 7 has the extending/contracting length for being separated from the ground surface by the extension by landing the longitudinal directional traveling plates 10 by the contraction.