To provide a stabilizer device excellent in travel stability, which continuously varies roll stiffness according to a load on an axle with a simple structure.

The stabilizer device includes a stabilizer 3 having a torsion bar portion 1 and arm portions 2, 2 with a sectional shape different in flexural rigidity in arbitrary cross sectional directions, respectively, which connect an end of the torsion bar portion 1 to a chassis frame and extend in a longitudinal direction of a vehicle. This stabilizer device includes an arm portion revolving mechanism capable of revolving the arm portions 2, 2 around an axis of the longitudinal direction and an actuator 10 actuated to rotate the arm portions 2, 2 at an arbitrary rotating position according to loading weight of the vehicle. The actuator 10 is driven by air from an air spring 12, where pressure varies in proportion to the load on the axle 28, and rotates the arm portions 2, 2 at the arbitrary rotating position by using this air.