To accurately reproduce and test dynamic response of an entire traveling cargo handling machine and float-up behavior of a leg in a simple shape.

The reduced-size testing device for the traveling cargo handling machine traveling on a rail while provided with legs on the front and rear sides of a lower part of an upper body and having a center of gravity on a front part side has a mass 51 for imitating the upper body of the traveling cargo handling machine; and front and rear legs F, R for supporting the mass 51. The leg F fixed to a front part near the center of gravity W of the mass 51 is turning legs 54a, 54b having a lower end connected onto a vibration base 52 by a hinge 53, and the leg R fixed to a rear part far from the center of gravity W of the mass 51 is a floating leg 55 having a lower end abutted on the vibration base 52. Principle of similarity with respect to primary vibration characteristic, position of the center of gravity, total mass and an inter-leg distance is made satisfied vis a vis the traveling type cargo work machine.