A suspension apparatus includes a pair of hydraulic cylinders and a valve device provided between an upper chamber and a lower chamber of each of the hydraulic cylinders and configured to establish and block communication between these chambers. The valve device includes a first passage and an extension-side damping force generation mechanism. Hydraulic oil flows out from the upper chamber into the first passage due to movement of a piston in a cylinder of the hydraulic cylinder. The extension-side damping force generation mechanism includes a damping valve and a back-pressure chamber. The damping valve is disposed in the first passage and generates a damping force by restricting a flow of the hydraulic oil generated due to a sliding movement of the piston. The back-pressure chamber applies an inner pressure thereof to the damping valve in a valve-closing direction.