Hydraulic system for a mobile stretcher with a hydraulic cylinder, a tank and a pump, wherein the hydraulic cylinder has a piston with at least one piston rod, a first working chamber and a second working chamber separated from the first working chamber by the piston, wherein the first working chamber is connected to the pump via a first line arrangement and the second working chamber is connected to the pump via a second line arrangement, wherein the first working chamber via the first line arrangement or the second working chamber via the second line arrangement can be selectively pressurized by the pump, wherein hydraulic fluid flows out of the first working chamber via the first line arrangement when pressure is applied to the second working chamber, in that the first line arrangement has a first check valve which can be opened when pressure is applied to the second line arrangement; and wherein hydraulic fluid flows out of the second working chamber via the second line arrangement when the first working chamber is pressurized, characterized in that the second line arrangement has a first branch line connected to the pump and a second branch line connected to the tank, a pressure valve is arranged in the second branch line and opening when the second line arrangement is pressurized, so that the pressure in the second line arrangement is limited to a pressure which is set at the pressure valve and is sufficient to open the first check valve, and an excess volume flow is directed to the tank via the pressure valve, the pressure set at the pressure valve being below the pump pressure, and wherein a second check valve is arranged in the first branch line, so that when the hydraulic cylinder is extended, the second working chamber is relieved via the pressure valve to the tank. wherein the hydraulic cylinder has a piston with at least one piston rod, a first working chamber and a second working chamber separated from the first working chamber by the piston, wherein the first working chamber is connected to the pump via a first line arrangement and the second working chamber is connected to the pump via a second line arrangement, wherein the first working chamber via the first line arrangement or the second working chamber via the second line arrangement can be selectively pressurized by the pump, wherein hydraulic fluid flows out of the first working chamber via the first line arrangement when pressure is applied to the second working chamber, in that the first line arrangement has a first check valve which can be opened when pressure is applied to the second line arrangement; and wherein hydraulic fluid flows out of the second working chamber via the second line arrangement when the first working chamber is pressurized, characterized in that the second line arrangement has a first branch line connected to the pump and a second branch line connected to the tank, a pressure valve is arranged in the second branch line and opening when the second line arrangement is pressurized, so that the pressure in the second line arrangement is limited to a pressure which is set at the pressure valve and is sufficient to open the first check valve, and an excess volume flow is directed to the tank via the pressure valve, the pressure set at the pressure valve being below the pump pressure, and wherein a second check valve is arranged in the first branch line, so that when the hydraulic cylinder is extended, the second working chamber is relieved via the pressure valve to the tank.