To improve rigidity with respect to rolling and convergence of the rolling.

This suspension device of bus comprises each of bellows 24 as an air spring disposed just under each of side members 10a (one of components of a frame 10) formed into an approximately linear shape and having a rear axle housing 28 attached thereto, and shock absorbers 30 interposed between the rear axle housing 28 and each of the side members 10a for damping vibration of the bellows 24. In this device, each of the shock absorbers 30 is disposed at an outside of a vehicle with respect to the side members 10a. By this constitution, since each mounting interval between the shock absorbers 30 becomes large, and mounting intervals of the shock absorbers becomes approximately equal to each other in a front and rear suspension devices, a front and back balance, rolling rigidity, and rolling convergence are improved, whereby riding quality and steering stability are enhanced.