Self-pumping hydropneumatic spring strut includes a working cylinder divided into first and second working spaces by a working piston carried on a hollow piston rod; a high pressure chamber and a low pressure chamber partially filled with hydraulic damping medium, the high pressure chamber having a gas cushion and being connected to the second working space; and a piston pump including a pump rod extending into the hollow piston rod, the pump rod having a bore connected to the low pressure chamber, an end provided with a suction valve inside the hollow piston rod, and a deregulating opening, which is closable as a function of position of the working piston in the working cylinder. An adjustable damping valve located outside the external tube has a first flow connection connected to the first working space, and a second flow connection connected to the second working space and the high pressure chamber.