A hydraulic assembly (5) for a cylinder head (2) of an internal combustion engine having a hydraulically variable valve train (1) is provided. A high pressure chamber (11), a medium pressure chamber (12) and a low pressure chamber (16), which serves as a hydraulic medium reservoir, are configured in the hydraulic assembly. The low pressure chamber communicates through a throttling point (17) with the medium pressure chamber, which throttling point is formed by a displaceable valve body (19) and, depending on the position of the valve body, provides flow cross-sections of different sizes in order to minimize the leakage out of the hydraulic assembly.