Hydraulic system, suspension assembly and vehicle

The invention provides a hydraulic system, a suspension assembly and a vehicle, and relates to the technical field of automobiles, the hydraulic system comprises a hydraulic cylinder and a hydraulic pump, and the hydraulic cylinder comprises a first cavity and a second cavity which are isolated from each other; the first cavity is connected with the hydraulic pump through a first branch, the second cavity is connected with the hydraulic pump through a second branch, and at least one of the first branch and the second branch can control connection and disconnection. Oil can directionally flow between the first cavity and the second cavity through a channel formed by the first branch, the second branch and the hydraulic pump. When at least one of the first branch and the second branch is disconnected, oil cannot directionally flow between the first cavity and the second cavity through a channel formed by the first branch, the second branch and the hydraulic pump. And the oil liquid can be controlled not to flow through the hydraulic pump, so that the pressure of the oil liquid is prevented from being reduced due to the fact that the oil liquid flows through the hydraulic pump and is shunted, the damping force borne by the oil liquid is prevented from being reduced, and the damping effect of the oil liquid on the piston is enhanced.