To buffer rocking impact about a center shaft of a front axle case, in addition to the vertical impact of a rocking frame.

In the suspension device of the traveling vehicle, a rear portion of the rocking frame 4 is supported on a front axle frame 3 of a vehicle body 2 front portion so as to rock about a supporting shaft 5 in a lateral direction. The front axle case 6 is supported on the rocking frame 4 so as to rock about a center shaft 7 in a fore-and-aft direction. Right and left suspension cylinders 8 coupling right and left both sides of the front axle frame 3 and the center shaft 7 of the front axle case 6 are provided.