A hydraulic system for hydraulically actuating a vertically adjustable ambulance lifting table used for receiving thereon a stretcher and adapted to be selectively switched to a cushioned mode of operation comprises a cylinder for actuating the lifting table, a hydraulic accumulator for cushioning the lifting table, a pump, a three-way valve, and a discharge valve connected to a reservoir of the hydraulic system on the outlet side thereof. In order to prevent the patient and/or the medical personnel from being exposed to danger by the lifting table when the above-mentioned hydraulic system is used, and even if the hydraulic system is actuated incorrectly, the three-way valve is in fluid connection with the pump and the hydraulic accumulator on the inlet side thereof and with the cylinder on the outlet side thereof, a valves is provided between the cylinder on the one hand and the hydraulic accumulator on the other, the valves is controlled such that it assumes an open position only if the pressure in the hydraulic accumulator exceeds the pressure within the cylinder by not more than a predetermined pressure difference, and the input side of the discharge valve is in fluid connection either with the hydraulic accumulator or with the cylinder depending on the pressure prevailing in the hydraulic accumulator relative to the pressure prevailing in the cylinder.