An equalizer bar itself serving as a suspension device of a track-type vehicle has spring effects imparted through torsional deformation relative to vertical oscillatory movements of track frames. Arm portions are fixed in directions opposite to each other in two ends of an equalizer bar main body. Free end portions of the arm portions are individually supported in the track frames to be rotatable in directions opposite to each other. The track frames are therefore regulated in the magnitudes of oscillatory movements according to the spring effects of the equalizer bar main body, whereby travel-time oscillations, oscillatory movements, and/or the like of the vehicle body are sufficiently restrained.